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This new paper aims to extend the authors’ previous contributions about open-loop aircraft flutter test to closed-loop aircraft flutter test by virtue of the proposed direct data–driven strategy. After feeding back the output signal to the input and introducing one feedback controller in the adding feedback loop, two parts, i.e. unknown aircraft flutter model and unknown feedback controller, exist in this closed-loop aircraft flutter system, simultaneously, whose input and output are all corrupted with external noise. Because of the relations between aircraft flutter model parameters and the unknown aircraft model, direct data–driven identification is proposed to identify that aircraft flutter model, then some identification algorithms and their statistical analysis are given through the authors’ own derivations. As the feedback controller can suppress the aircraft flutter or guarantee the flutter response converge to one desired constant value, the direct data–driven control is applied to design that feedback controller only through the observed data sequence directly. Numerical simulation results have demonstrated the efficiency of the proposed direct data–driven strategy. Generally, during our new information age, direct data–driven strategy is widely applied around our living life.

First, consider one more complex closed loop stochastic aircraft flutter model, whose input–output are all corrupted with external noise. Second, for the identification problem of closed-loop aircraft flutter model parameters, new identification algorithm and some considerations are given to the corresponding direct data–driven identification. Third, to design that feedback controller, existing in that closed-loop aircraft flutter model, direct data–driven control is proposed to design the feedback controller, which suppresses the flutter response actively.

A novel direct data–driven strategy is proposed to achieve the dual missions, i.e. identification and control for closed-loop aircraft flutter test. First, direct data–driven identification is applied to identify that unknown aircraft flutter model being related with aircraft flutter model parameters identification. Second, direct data–driven control is proposed to design that feedback controller.

To the best of the authors’ knowledge, this new paper extends the authors’ previous contributions about open-loop aircraft flutter test to closed-loop aircraft flutter test by virtue of the proposed direct data–driven strategy. Consider the identification problem of aircraft flutter model parameters within the presented closed loop environment, direct data–driven identification algorithm is proposed to achieve the identification goal. Direct data–driven control is proposed to design the feedback controller, i.e. only using the observed data to design the feedback controller.

Though there has been steady growth in the automobile sector in India, India is still a player of little consequence in global auto production. Despite total quality management (TQM) playing an increasingly important role in the survival and growth of companies in the automobile sector, the dynamic interactions among its subsystems have not received due attention in the literature. Based on the Malcolm Baldrige National Quality Award model, this paper develops causal relationships among the different variables that represent “enablers” and “results” – operating within 44 identified feedback loops. Of these loops, 33 are positive and 11 are negative. The resulting causal loop diagram provides an insight into understanding the dynamic interactions among TQM subsystems which helps identify proactive action in implementing the TQM philosophy.

The purpose of this paper is to report the empirical findings of a survey aimed to investigate the need to improve cross‐phase learning between design and construction. Through exploring the need to introduce a design‐construction feedback loop, combined with the barriers against its development, an expansion of knowledge surrounding the deficiencies of current practice is provided.

The paper reports the results from an online survey conducted in spring 2011 targeted at experienced personnel in the planning, design, construction and facilities management phases of healthcare infrastructure projects.

The current approach of detecting and correcting errors is significantly hindering the extent to which learning from previous experiences is taking place. It is shown that improved integration between design and construction is required in the form of improved feedback if continuous improvement in the areas of efficiency, quality, value and general learning from previous experiences/projects is to be achieved.

The focused population of this study limits the extent to which the findings can be generalised. However, it is viewed that this context is potentially one of the most complex and unique project participant arrangements to overcome. Therefore if the need and ability to share learning outcomes across such a complex arrangement can be achieved, then it may be easier within traditional arrangements.

The practical implications of moving away from single‐loop learning towards a double‐loop learning approach are provided.

This paper identifies that there is a distinct need for further efforts to be applied in the area of improving feedback between the phases of design and construction.

This paper aims to depict the evolution of the relationship between tourism and the night-time economy (NTE) from 1946 to 2095.

This paper enables the feedback loop concept rooted in general system theory to identify positive and negative feedback loops between tourism and the NTE. The study is based on selective literature on the topic.

The paper recognises the volatility of positive and negative loops in the past and the dominance of positive feedback loops in the future. This paper also identifies the primary triggers of the feedback loops as technological, economic, environmental, political, social and market.

Selective literature review and abstracting from the impact of other industries on the recognised feedback loops are the main limitations of the study.

The development of both tourism and the NTE should be considered and planned just through the prism of their feedback loops.

The feedback loop concept is proposed to explain the general logic of dynamics of the relationship between tourism and the NTE.

Briefly reviews the standard Poisson distribution and then examines a set of derivative, modified Poisson distributions for testing hypotheses derived from positive deviation‐amplifying feedback models, which do not lend themselves to ordinary statistically based hypothesis testing. The “reinforcement” or “contagious” Poisson offers promise for a subset of such models, in particular those models with data in the form of rates (rather than magnitudes). The practical difficulty lies in distinguishing reinforcement effects from initial heterogeneity, since both can form negative binomial distributions, with look‐alike data. Illustrates these difficulties, and also opportunities, for various feedback models employing the self‐fulfilling prophecy, and especially for confidence loops, which incorporate particular self‐fulfilling prophecies as part of a larger dynamic process. Describes an actual methodology for testing hypotheses regarding confidence loops with the aid of a “reinforcement” Poisson distribution, as well as its place within sociocybernetics.

Although knowledge transfer is generally conceived as a two‐way process in which knowledge is transferred to and from the knowledge source, research has tended to focus on the first part of the process and neglect the second part. This study aims to examine the feedback loop and how knowledge is transferred from the knowledge receiver to the knowledge source.

The paper relies on interviews and archival records to conduct an in‐depth case study of cross‐border knowledge transfer work carried out by a Canadian non‐profit organization.

The paper finds that by learning about receivers' knowledge, background and learning styles, as well as their social context or learning environment, such as language, culture, tradition and history, “source” persons are in fact able to acquire for themselves valuable new knowledge. This in turn assists both the source and receiver to establish shared understandings, thereby facilitating a more effective knowledge transfer thus enhancing learning for both the source and receiver.

Given that this is a case study of one organization, the findings of this study may not be readily generalizable to other organizations, or settings. Despite this limitation, the study raises some important questions for further investigation and contributes to existing research on intercultural knowledge transfer.

Individuals involved in knowledge transfer who pay attention to the feedback loop can better perform their roles and also improve their knowledge.

It has been acknowledged in the literature that expatriates engage in extensive learning while transferring knowledge in their overseas assignments. However, little research has examined what they have learned, how they learn, and the benefits of such learning. This research suggests that knowledge sources can enhance their own knowledge as well as improve knowledge transfer to recipients by nurturing feedback loops.

The purpose of this paper is to investigate airfoil’s tonal noise reduction mechanism when deploying surface irregularities, such as surface waviness by means of spatial stability analyses.

Flow field calculations over smooth and wavy-surface NACA 0012 airfoils at 2° angle of attack and at Reynolds number of 200,000 are performed using the large eddy simulation (LES) approach. Three geometrical configurations are considered: a smooth NACA 0012 airfoil, wavy surface on the suction side (SS) and wavy surface on the pressure side (PS). The spatial stability analyses using the LES-generated flow fields are conducted and validated against the Orr-Sommerfeld stability analysis for the smooth airfoil configuration.

The spatial stability analyses show that inclusion of the wavy-type modification on the SS of the airfoil does not lead to altering of the acoustic feedback loop mechanism, with respect to the mechanism observed for the smooth airfoil configuration. In contrast, applying the surface modifications to the airfoil PS leads to a significant reduction of the amplification range of disturbances in the vicinity of the trailing edge for the frequency of the acoustic feedback loop mechanism.

The spatial analyses using, for example, LES-generated flow fields can be widely used to determine acoustic sources and associated distributions of amplifications for a wide range of applications in the aeroacoustics.

The spatial stability analysis approach based on flow fields computed a priori using the LES method has been introduced, validated and used to determine behaviour of the acoustic feedback loop when accurate reconstruction of geometry effects is required.