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Obstacle and wind field are common environmental factors for mini unmanned helicopter (MUH) flight. This paper aims to develop a trajectory planning approach guiding MUH to avoid static and dynamic obstacles and to fly in steady uniform or boundary-layer wind field.

An optimal control model including a nonlinear flight dynamics model and a cubic obstacle model is established for MUH trajectory planning. Radau pseudospectral method is used to generate the optimal trajectory.

The approach can plan reasonable obstacle-avoiding trajectories in obstacle and windy environments. The simulation results show that high-speed wind fields increase the flight time and fluctuation of control inputs. If boundary-layer wind field exists, the trajectory deforms significantly and gets closer to the ground to escape from the strong wind.

The key innovations in this paper include a cubic obstacle model which is straightforward and practical for trajectory planning and MUH trajectory planning in steady uniform wind field and boundary-layer wind field. This study provides an efficient solution to the trajectory planning for MUH in obstacle and windy environments.

Applying discrete linear optimal control to robot manipulators faces two challenging problems, namely nonlinearity and uncertainty. This paper aims to overcome nonlinearity and uncertainty to design the discrete optimal control for electrically driven robot manipulators.

Two novel discrete optimal control approaches are presented. In the first approach, a control-oriented model is applied for the discrete linear quadratic control while modeling error is estimated and compensated by a robust time-delay controller. Instead of the torque control strategy, the voltage control strategy is used for obtaining an optimal control that is free from the manipulator dynamics. In the second approach, a discrete optimal controller is designed by using a particle swarm optimization algorithm.

The first controller can overcome uncertainties, guarantee stability and provide a good tracking performance by using an online optimal algorithm whereas the second controller is an off-line optimal algorithm. The first control approach is verified by stability analysis. A comparison through simulations on a three-link electrically driven robot manipulator shows superiority of the first approach over the second approach. Another comparison shows that the first approach is superior to a bounded torque control approach in the presence of uncertainties.

The originality of this paper is to present two novel optimal control approaches for tracking control of electrically driven robot manipulators with considering the actuator dynamics. The novelty is that the proposed control approaches are free from the robot's model by using the voltage control strategy. The first approach is a novel discrete linear quadratic control design supported by a time-delay uncertainty compensator. The second approach is an off-line optimal design by using the particle swarm optimization.

The purpose of this paper is to present a separable identification algorithm for a multiple-input single-output (MISO) continuous-time (CT) system.

This paper proposes an optimal method for the identification of MISO CT systems with unknown time delays by using the Simplified Refined Instrumental Variable method.

Simulations results are presented to show the performance of the proposed approach in the presence of additive output measurement noise.

This paper presents an optimal and robust method to separable delays and parameter identification of a MISO CT system with unknown time delays from sampled input/output data.

Cognitive literary criticism is introduced as a bridge between cognitive approaches to the study of persuasion, and literary traditions in consumer research. As a successor to reader-response theory, cognitive literary theory focuses on the cognitive processes of interpretation, while keeping an eye on the aesthetic properties of the text. Paradigmatically cautious researchers might shy away from attempts to marry positivist cognitive constructs to interpretivist cultural theory, but this chapter argues that these qualms also conceal missed opportunities for the study of persuasion.

Insights from cognitive literary criticism are demonstrated at the hand of a LEGO ad.

Theory of mind and conceptual blending are crucial cognitive skills involved in the interpretation of persuasive texts.

Most research to date has kept literary and cognitive approaches to persuasion separate, black-boxing the processes of persuasion. This chapter argues for a revitalization of interest in aesthetic detail, informed by insights from cognitive science.

Brand equity has been highlighted as a crucial element in differentiating products and achieving competitive advantage. Recent studies reflect the gradual rise in interest in the importance of building brand equity linked to the store. However, empirical evidence about the antecedents of store brand equity is still scarce, particularly on the retailer’s corporate social responsibility behavior. This chapter aims to analyze the influence of the retailer’s commitment to sustainable development (RCSD) and the credibility of the retailer’s communications on the overall store brand equity. Focusing on two samples of hypermarket customers in France and Spain, the findings provide evidence on the importance of the RCSD regarding employees, society, and environment, as well as the effectiveness of credible communications to generate store brand equity. Results are consistent for France and Spain.

To design effective and practical controllers that use the adaptive fuzzy approaches and are applicable to helicopters.

Based on Takagi‐Sugeno fuzzy systems, a new direct adaptive fuzzy control scheme is developed for a class of nonlinear multiple‐input‐multiple‐output systems. A simple observer is designed to generate an error signal for the adaptive law. The system states of the system are not required to be available for measurement.

The overall adaptive scheme guarantees all the signals involved being uniformly bounded in the Lyapunov sense.

The implementation of this research work needs further investigation.

The simplicity of the design algorithm facilitates the application of the design to helicopters by the use of Matlab.

Experimental results of a two degree of freedom helicopter are presented to confirm the usefulness of the proposed new control scheme.

Considers the mathematical modelling of sewing machines. The machine with a rotary hook and with a feed mechanism driven by two triangle cams is studied. The behaviour of the system is described by a set of non‐linear autonomous ordinary differential equations. It is shown that, due to the timing belt extensibility, the actual relative position of the needle and the hook is different from that expected. This difference is a result of the conflict between the almost constant speed of the hook shaft and the fluctuating speed of the crank‐shaft caused by the reciprocating motion of working elements. The vibration of the belt increases with speed. Resonance increase of vibrations takes place when the shaft speed is equal to natural frequency or its fraction 1/n for n = 1, 2, 3, 4, 5.

The purpose of the paper is to present an approach to detect and isolate the aircraft sensor and control surface/actuator failures affecting the mean of the Kalman filter innovation sequence.

The extended Kalman filter (EKF) is developed for nonlinear flight dynamic estimation of an F‐16 fighter and the effects of the sensor and control surface/actuator failures in the innovation sequence of the designed EKF are investigated. A robust Kalman filter (RKF) is very useful to isolate the control surface/actuator failures and sensor failures. The technique for control surface detection and identification is applied to an unstable multi‐input multi‐output model of a nonlinear AFTI/F‐16 fighter. The fighter is stabilized by means of a linear quadratic optimal controller. The control gain brings all the eigenvalues that are outside the unit circle, inside the unit circle. It also keeps the mechanical limits on the deflections of control surfaces. The fighter has nine state variables and six control inputs.

In the simulations, the longitudinal and lateral dynamics of an F‐16 aircraft dynamic model are considered, and the sensor and control surface/actuator failures are detected and isolated.

A real‐time detection of sensor and control surface/actuator failures affecting the mean of the innovation process applied to the linearized F‐16 fighter flight dynamic is examined and an effective approach to isolate the sensor and control surface/actuator failures is proposed. The nonlinear F‐16 model is linearized. Failures affecting the covariance of the innovation sequence is not considered in the paper.

An approach has been proposed to detect and isolate the aircraft sensor and control surface/actuator failures occurred in the aircraft control system. An extended Kalman filter has been developed for the nonlinear flight dynamic estimation of an F‐16 fighter. Failures in the sensors and control surfaces/actuators affect the characteristics of the innovation sequence of the EKF. The failures that affect the mean of the innovation sequence have been considered. When the EKF is used, the decision statistics changes regardless the fault is in the sensors or in the control surfaces/actuators, while a RKF is used, it is easy to distinguish the sensor and control surface/actuator faults.

The purpose of this paper is to propose an adaptive robust controller for coupled attitude and orbit control of rigid spacecraft based on dual quaternion in the presence of external disturbances and model uncertainties.

First, based on dual quaternion, a theoretical model of the relative motion for rigid spacecraft is introduced. Then, an adaptive robust controller which can realize coordinated control of attitude and orbit is designed in the existence of external disturbances and model uncertainties.

This paper takes advantage of the Lyapunov function which can guarantee the asymptotic stabilization of the whole system in the existence of parameters uncertainties. Simulation results show that the proposed controller is feasible and effective.

This paper proposes a coupled attitude and orbit adaptive robust controller based on dual quaternion. Simulation results demonstrate that the proposed controller can achieve higher control performance in the presence of parameters uncertainties.

We examine the behavior of the Russian stock market as one of the leading indices of economic health, reflecting investors’ expectations about future returns. The sample period includes the global financial crisis, a recovering period, and the recent crisis in the Russian economy 2014–2015.

We assume that the Russian stock market strongly depends on the global market, but the market is not fully integrated. This chapter investigates whether specific risk factors such as high dependence of the Russian economy on oil prices and currency volatility are priced in the Russian stock market, using International CAPM with time-variant parameters and conditional heteroskedasticity. The results show that the global financial crisis has had a profound negative impact on the Russian market, and that the expected return and liquidity has declined. The risk of investing in the Russian market is estimated as higher than in the developed market and even in other emerging markets after the global recession. We find that oil price exposure and currency risk to be priced in the Russian stock market and indicate that international investors require higher compensation for bearing these risks. The price of the currency risk has decreased since the implementation of the floating exchange rate regime by the Central Bank of Russia in 2014, but still significant.

Some opportunities to overcome the present stagnation and drive for a sustainable development are discussed.