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The purpose of this paper is to design a hybrid robust tracking controller based on an improved radial basis function artificial neural network (IRBFANN) and a novel extended-state observer for a quadrotor system with various model and parametric uncertainties and external disturbances to enhance the resiliency of the control system.

An IRBFANN is introduced as an adaptive compensator tool for model and parametric uncertainties in the control algorithm of non-singular rapid terminal sliding-mode control (NRTSMC). An exact-time extended state observer (ETESO) augmented with NRTSMC is designed to estimate the unknown exogenous disturbances and ensure fast states convergence while overcoming the singularity issue. The novelty of this work lies in the online updating of weight parameters of the RBFANN algorithm by using a new idea of incorporating an exponential sliding-mode effect, which makes a remarkable effort to make the control protocol adaptive to uncertain model parameters. A comparison of the proposed scheme with other conventional schemes shows its much better performance in the presence of parametric uncertainties and exogenous disturbances.

The investigated control strategy presents a robust adaptive law based on IRBFANN with a fast convergence rate and improved estimation accuracy via a novel ETESO.

To enhance the safety level and ensure stable flight operations by the quadrotor in the presence of high-order complex disturbances and uncertain environments, it is imperative to devise a robust control law.

A new idea of incorporating an exponential sliding-mode effect instead of conventional approaches in the algorithm of the RBFANN is used, which makes the control law resistant to model and parametric uncertainties. The ETESO provides rapid and accurate disturbance estimation results and updates the control law to overcome the performance degradation caused by the disturbances. Simulation results depict the effectiveness of the proposed control strategy.

This study aims to achieve the post-stall pitching maneuver (PSPM) and decrease the deflection frequency of aircraft actuators controlled by the robust backstepping method based on event-triggered mechanism (ETM), nonlinear disturbance observer (NDO) and dynamic surface control (DSC) techniques.

To estimate unsteady aerodynamic disturbances (UADs) to suppress their adverse effects, the NDO is designed. To avoid taking the derivative of the virtual control law directly and eliminate the coupling term of the system states and dynamic surface errors in the stability analysis, an improved DSC is developed. Combined with the NDO and DSC techniques, a robust backstepping method is proposed to achieve the PSPM. Furthermore, to decrease the deflection frequency of the aircraft actuators, a state-dependent ETM is introduced.

An ETM-and-NDO-based backstepping method with an improved DSC technique is developed to achieve the PSPM and decrease the deflection frequency of aircraft actuators. And simulation results are presented to verify the effectiveness of the proposed paper.

Few studies have been conducted on the control of the PSPM in which the lateral and longitudinal attitude dynamics are coupled with each other considering the UADs. Moreover, the mechanism that can decrease the deflection frequency of aircraft actuators is rarely developed in existing research. This study proposes an ETM-and-NDO-based backstepping scheme to address these problems with satisfactory performance of the PSPM.

SELECTED by the European Council of the International Committee for Scientific Management (C.I.O.S.) to organise the first European Conference devoted entirely to management problems, the British Institure of Management has risen nobly to the occasion with a three‐day programme full of interest and variety within the main framework of the conference theme. It is hoped that representatives from no less than fourteen European countries will attend.

Aim of the present monograph is the economic analysis of the role of MNEs regarding globalisation and digital economy and in parallel there is a reference and examination of some legal aspects concerning MNEs, cyberspace and e‐commerce as the means of expression of the digital economy. The whole effort of the author is focused on the examination of various aspects of MNEs and their impact upon globalisation and vice versa and how and if we are moving towards a global digital economy.

Each of the four objectives can be applied within the military training environment. Military training often requires that soldiers achieve specific levels of performance or proficiency in each phase of training. For example, training courses impose entrance and graduation criteria, and awards are given for excellence in military performance. Frequently, training devices, training media, and training evaluators or observers also directly support the need to diagnose performance strengths and weaknesses. Training measures may be used as indices of performance, and to indicate the need for additional or remedial training.

THE accountant is the latest competitor for management power. The Institute of Cost & Works Accountants—the value of whose Associate qualification we acknowledge—has re‐cast its requirements for the grade of Fellowship. Cost Accountants' or for that matter many other kinds of accountant, are now invited to sit for the Fellowship examination, the syllabus for which has just been published. This comprises the now familiar: Management—Factory and Distribution, Statistical Method, Advanced Cost Accountancy, Company Law, Management Accountancy and the Economic Aspects of Industry and Commerce. (The Management Section includes Motion & Time Study). Assuming that they are successful in this and that they satisfy a Reviewing Board of the adequacy of their experience, they may then call themselves “Management Accountants”.

The economic science is again in a crisis and a new solution prolegomena to any future study in economics, finance and other social sciences has just been published by the International Institute of Social Economics in care of the MCB University Press in England. The roots of the major financial and economic problems of our time lie in an open conflict between theory and practice. In the 1930s and before the conflict was between classical theory and given realities. In the 1990s the conflict appears between the now prevailing modern, Keynesian theory and the actual realities. In addition during the twentieth century a great argument developed between the two schools of thought, argument which is not yet settled. In one sentence, the prolegomena tried and was successful to solve the conflict between theory and practice and the big doctrinal dispute of the twentieth century. It was a struggle of research and observation over half a century between 1947 and 1997.

At the time they occurred, the savings and loan insolvencies were considered the worst financial crisis since the Great Depression. Contrary to what was then believed, and in sharp contrast with 2007–2009, they in fact had little macroeconomic significance. Savings and Loan (S&L) remediation cost between 2 percent and 3 percent of Gross Domestic Product (GDP), whereas the Troubled Asset Relief Program (TARP) and the conservatorships of Fannie and Freddie actually made money for the US Treasury. But the direct cost of government remediation is largely irrelevant in judging macro significance. What matters is the cumulative output loss associated with and plausibly caused by failing financial institutions. I estimate output losses for 1981–1984, 1991–1998, and 2007–2026 (the latter utilizing forecasts and projections along with actual data through 2015) and, for a final comparison, 1929–1941. The losses associated with 2007–2009 have been truly disastrous – in the same order of magnitude as the Great Depression. The S&L failures were, in contrast, inconsequential. Macroeconomists and policy makers should reserve the word crisis for financial disturbances that threaten substantial damage to the real economy, and continue efforts to identify in advance financial institutions which are systemically important (SIFI), and those which are not.

MILLIONS of pounds have been recklessly thrown away by the naive Government on useless so‐called defence contracts. The greatest loss has been sustained by the aircraft industry and anyone who has had any experience at all of that industry will find nothing remarkable in such a statement.