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Winglets play a major role in saving fuel costs because they reduce the lift-induced drag formed at the wingtips. The purpose of this paper is to obtain the best orientation of the winglet for the Office National d’Etudes et de Recherches Aérospatiales (ONERA) M6 wing at Mach number 0.84 in terms of lift to drag ratio.

A computational fluid dynamics analysis of the wing-winglet configuration based on the ONERA M6 airfoil on drag reduction for different attack angles at Mach 0.84 was performed using analysis of systems Fluent. First, the best values of cant and sweep angles in terms of aerodynamic performance were selected by performing simulations. The analysis included cant angle values of 30°, 40°, 45°, 55°, 60°, 70° and 75°, while for the sweep angles 35°, 45°, 55°, 65° and 75° angles were used. The aerodynamic performance was measured in terms of the obtained lift to drag ratios.

The results showed that slight alternations in the winglet configuration can improve aerodynamic performance for various attack angles. The best lift to drag ratio for the winglet was achieved at a cant angle of 30° and a sweep angle of 65°, which caused a 5.33% increase in the lift to drag ratio. The toe-out angle winglets as compared to the toe-in angles caused the lift to drag ratio to increase because of more attached flow at its surface. The maximum value of the lift to drag ratio was obtained with a toe-out angle (−5°) at an angle of attack 3° which was 2.53% greater than the zero-toed angle winglet.

This work is relatively unique because the cant, sweep and toe angles were analyzed altogether and led to a significant reduction in drag as compared to wing without winglet. The wing model was compared with the results provided by National Aeronautics and Space Administration so this validated the simulation for different wing-winglet configurations.

The purpose of this paper is to present a novel approach based on the differential search (DS) algorithm integrated with the adaptive network-based fuzzy inference system (ANFIS) for unmanned aerial vehicle (UAV) winglet design.

The winglet design of UAV, which was produced at Faculty of Aeronautics and Astronautics in Erciyes University, was redesigned using artificial intelligence techniques. This approach proposed for winglet redesign is based on the integration of ANFIS into the DS algorithm. For this purpose, the cant angle (c), the twist angle (t) and taper ratio (λ) of winglet are selected as input parameters; the maximum value of lift/drag ratio (E_max) is selected as the output parameter for ANFIS. For the selected input and output parameters, the optimum ANFIS parameters are determined by the DS algorithm. Then the objective function based on optimum ANFIS structure is integrated with the DS algorithm. With this integration, the input parameters for the E_max value are obtained by the DS algorithm. That is, the DS algorithm is used to obtain both the optimization of the ANFIS structure and the necessary parameters for the winglet design. Thus, the UAV was reshaped and the maximum value of lift/drag ratio was calculated based on new design.

Considerable improvements on the max E are obtained through winglet redesign on morphing UAVs with artificial intelligence techniques.

It takes a long time to obtain the optimum E_max value by the computational fluid dynamics method.

Using artificial intelligence techniques saves time and reduces cost in maximizing E_max value. The simulation results showed that satisfactory E_max values were obtained, and an optimum winglet design was achieved. Thus, the presented method based on ANFIS and DS algorithm is faster and simpler.

The application of artificial intelligence methods could be used in designing more efficient aircrafts.

The study provides a new and efficient method that saves time and reduces cost in redesigning UAV winglets.

This study considers the five factors of a car rotation system: angle (F1), arm length (F2), toe in and out (F3), width (F4) and length (F5). The purpose of this paper is to fine tune the design so it produces the smoothest response to various rotation angles.

In the case of Ackerman’s principle, the response surface methodology (RSM) was used to analyze data when encountering different quality characteristics at various rotation angles.

In this study, RSM was used to obtain the best factor and the best reaction value for the five factors of a car rotation system.

In this study, the four-wheel steering of a car is taken as an example. When the current wheel is turned, the intersection of the left and right wheels of the front axle falls on the extension line of the rear wheel. In this case, the steering will be the smoothest. In this example, we selected angle (F1), arm length (F2), toe in and out (F3), width (F4) and length (F5) as experimental factors, hoping to satisfy the Ackerman principle.

Traditionally, when dealing with four-wheel steering problems, solutions may be based on past experience or on new information used to formulate R&D plans. In this study, the combination of statistical factors and optimization is used to find the optimal combination of factors and the relationship between factors.

In the past, most literature relied on kinematics to study the car rotation system due to a lack of experimental design and analysis concepts. However, this study aims to achieve the above goals in finding the solution, which can be used to predict reaction values.

The purpose of this paper is to complete fatigue analysis of welded joints considering both the crack initiation sites and crack coalescence, and to generate virtual welded specimens for computer simulation of fatigue life on a specimen-by-specimen basis; knowledge regarding the weld toe stress concentration factor (SCF) sequence is essential. In this study, attempts were made to analyze the sequence and to find a simple method to generate the sequence using computers.

Laser scanning technique was used to acquire the real three-dimensional weld toe geometry of welded specimens. The scanned geometry was digitally sectioned, and three-dimensional finite element (FE) models of the scanned specimens were constructed and the weld toe SCF sequence was calculated. The numbers in the sequence were analyzed using a simple autoregression model and the statistical properties of the sequence were acquired.

The autoregression analysis showed the value of a weld toe SCF is linearly related to its neighboring factor with a high correlation. When a factor value at a toe location is known, the neighboring factor can be simulated by a simple linear equation with a random residual. The weld toe factor sequence can thus be formed by repeatedly using the linear equation with a residual. The generated sequence exhibits close statistical properties to those of the real sequence obtained from FE results.

When the weld toe SCF sequence is known, it is possible to foresee potential crack locations and the subsequent crack coalescence. The results of the current study will be the foundation for the future work on fatigue analysis of welded joints considering the effects of crack initiation site and crack coalescence.

The weld toe SCF sequence was rarely discussed previously because of a lack of the available data. The current study is the first work to investigate the statistical properties of the sequence and found that a simple autoregression equation can be used to perform the analysis. This study is also the first work that successfully generates a weld toe SCF sequence, which can be used to simulate virtual welded specimens.

The purpose of this paper is to generate a virtual knee angle reference to be followed by a knee prosthesis control, using an adaptive central pattern generator (CPG). Also, to study the feasibility of this approach to implement a continuous control strategy on the prosthesis.

A CPG based on amplitude controlled phase oscillators (ACPOs) to track the current percentage of gait cycle on the prosthesis is proposed. Then, the virtual knee angle reference is generated along gait cycle, by interpolation with the corresponding angle of a sound knee. The structure and coupling of the CPG, as well as the control strategy are presented.

The coupling of the CPG with real gait on the prosthesis was proven, regardless of gait speed. Also, it was found that the maximum knee angle reached during walking is proportional to gait speed. Finally, generation of virtual knee angle reference to be followed by a prosthesis is demonstrated.

As only one event detected along gait cycle was used to update the CPG phase, the response to gait speed changes might be slow. Updating the CPG with more events remains for a future work.

The coupling of the CPG with real gait on the prosthesis results in a continuous gait cycle tracker, useful for any control strategy to be applied.

It is the first time a bio‐inspired concept as CPGs is applied to the prosthetic field. This could mean the beginning of a new era of cybernetic prostheses, which reproduce the lost limb and also the control functions of it.

This paper aims to explore the challenges and opportunities of blockchain technology adoption from the lens of the technological–organisational–environmental (TOE) framework for operational excellence in the UK automotive industry context.

The research methodology of this study follows a systematic review approach, which analyses existing academic published research papers in the top 35 academic journals. There was no specific timeframe established for this study and shortlisting the articles through a set of used keywords. A sample of 71 articles was shortlisted and analysed to provide a discussion on technological and management challenges and opportunities of blockchain adoption from the lens of the TOE framework for operational excellence.

The findings of this study present significant theoretical and managerial implications and deep understanding for firms seeking to understand the challenges and opportunities of blockchain adoption for their operational excellence.

The systematic literature approach was considered for the present study to explore existing academic papers on technological and management challenges and opportunities from the lens of TOE framework for operational excellence, whereas a more specified method meta-analysis can be considered for future research. The study has been explored in the UK automotive industry context, which has been considered as the limitation of generalisation across countries and industries.

This paper represents the most comprehensive literature study related to the technological and management challenges and opportunities of blockchain from the TOE framework angle for operational excellence.

The paper aims to address the organizational transformation of firms for value creation resulting from cloud computing (CC).

With reference to the theory of organizational fit, we modeled organizational transformation as a function of five aspects of CC practice: functionality, data management, roles and competences of information technology services, control and organizational culture. The output variable was tested against a set of input variables defined with reference to the technology–organization–environment (TOE) and technology acceptance model (TAM). Based on a sample of 487 companies in seven countries in Europe, Asia, and the United States, the authors distinguished two groups of firms: transformational and hyper transformational.

The results highlight the key factors that determine whether a firm falls into one of these two groups, and include perceived usefulness and perceived ease of use, complexity and compatibility of CC technology, and adequacy of resources. Top management support and government policy are found to only play a role for the transformational group while, surprisingly, vendor support had no impact for either group.

This research contributes to the literature on the role of digital transformation in value creation and on digitization of firms and organizational design, notably by considering the contribution of CC to the organizational dimension. To the best of the authors’ knowledge, this is the first study to make the link between TOE and TAM models and organizational fit theory, thereby going beyond the general approach to adoption found in information system research.

IN the following notes the phenomenon of ground looping (which may be defined as an uncontrollable fast turn on the ground) is briefly analysed by semi‐technical methods. The analysis has been restricted to a condition which in the opinion of experienced pilots causes trouble most frequently: namely, a landing with dead stick, when there is no slipstream available to make the rudder more effective. The equations of lateral motion for an aeroplane in contact with the ground have been written clown as an introduction to more thorough study. Finally, certain tentative conclusions have been drawn for application in aeroplane design with a view to eliminating or at least reducing ground loop tendencies.

This study evaluated the determinants of augmented reality (AR) adoption in Malaysia's travel and tour operator sectors through an integrated technology-organization-environmental (TOE) and diffusion of innovation (DOI) model.

The TOE and DOI were considered the primary theoretical models but are combined and extended by including few additional variables. Data were collected from 220 respondents of travel and tour operating businesses in Malaysia and analyzed by applying PLS structural equation model technique.

The empirical results established that perceived cost, relative advantages, complexity and compatibility, observability, competitor pressure, value alignment, customer pressure, and trialability are positively connected with the behavioral intention except for external support. The results reveal that value alignment partially mediates the association between relative advantages and behavioral intention, complexity and behavioral intention, compatibility and behavioral intention, perceived cost and behavioral intention except in between trialability and observability.

This research is unique as the value alignment construct is included in the model, and thus it fulfills the literature gap by adding the mediation construct. This study contributes to enhancing AR's understanding of the Malaysian travel and tour operator industry through the lenses of owners or managers. It offers an integrated model that combines the TOE and DOI models, rare in this sector, and can be replicated or extended with validated scales.

Although studies have investigated reasons for software as a service (SaaS) adoption, it is unclear how firm-level SaaS use impacts future SaaS intentions. The purpose of this paper is to propose a theoretical model that integrates the technology-organization-environment framework, institutional theory, diffusion-of-innovation theory and the opportunity-risk framework to analyze the drivers of SaaS use and its continuance intention.

The authors evaluated the direct, moderating and mediating effects of determinants on SaaS continuance intentions using structural equation modeling and data from 301 firms.

Results found that top management support and normative pressures influenced SaaS use. Cost saving and security concerns were direct predictors of perceived opportunities and perceived risks, respectively. Perceived opportunities and risks and actual SaaS use influenced SaaS continuance. Interestingly, perceived opportunities were found to be a negative moderator on the relationship between SaaS use and SaaS continuance.

The results reveal insightful and controversial findings for SaaS research.