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The purpose of this paper is to design an output-feedback algorithm based on low-power observer (LPO), robust chattering-free controller and nonlinear disturbance observer (DO) to achieve trajectory tracking of quadrotor in the Cartesian plane.

To achieve trajectory tracking control, firstly the decoupled rotational and translational model of quadrotor are modified by introducing backstepped state-space variables. In the second step, robust integral sliding mode control is designed based on the proportional-integral-derivative (PID) technique. In the third step, a DO is constructed. In next step, the measurable outputs, i.e. rotational and translational state variables, are used to design the LPO. Finally, in the control algorithm all state variables and its rates are replaced with its estimates obtained using the state-observer.

The finding includes output-feedback control (OFC) algorithm designed by using a LPO. A modified backstepping model for rotational and rotational systems is developed prior to the design of integral sliding mode control based on PID technique. Unlike traditional high-gain observers (HGO), this paper used the LPO for state estimation of quadrotor systems to solve the problem of peaking phenomenon in HGO. Furthermore, a nonlinear DO is designed such that it attenuates disturbance with unknown magnitude and frequency. Moreover, a chattering reduction criterion has been introduced to solve the inherited chattering issue of controllers based on sliding mode technique.

This paper presents input and output data-driven model-free control algorithm. That is, only input and output of the quadrotor model are required to achieve the trajectory tracking control. Therefore, for practical implementation, the number of on-board sensor is reduced.

Although extensive research has been done for designing OFC algorithms for quadrotor, LPO has never been implemented for the rotational and translational state estimations of quadrotor. Furthermore, the mathematical model of rotational and translational systems is modified by using backstepped variables followed by the controller designed using PID and integral sliding mode control technique. Moreover, a DO is developed for attenuation of disturbance with unknown bound, magnitude and frequency.

This book is a policy proposal aimed at the democratic left. It is concerned with gradual but radical reform of the socio‐economic system. An integrated policy of industrial and economic democracy, which centres around the establishment of a new sector of employee‐controlled enterprises, is presented. The proposal would retain the mix‐ed economy, but transform it into a much better “mixture”, with increased employee‐power in all sectors. While there is much of enduring value in our liberal western way of life, gross inequalities of wealth and power persist in our society.

Power‐electronic systems have been playing a significant role in the integration of large‐scale wind turbines into power systems due to the fact that during the past three decades power‐electronic technology has experienced a dramatic evolution. This second part of the paper aims to focus on a comprehensive survey of power converters and their associated control systems for high‐power wind energy generation applications.

Advanced control strategies, i.e. field‐oriented vector control and direct power control, are initially reviewed for wind‐turbine driven doubly fed induction generator (DFIG) systems. Various topologies of power converters, comprising back‐to‐back (BTB) connected two‐ and multi‐level voltage source converters (VSCs), BTB current source converters (CSCs) and matrix converters, are identified for high‐power wind‐turbine driven PMSG systems, with their respective features and challenges outlined. Finally, several control issues, viz., basic control targets, active damping control and sensorless control schemes, are elaborated for the machine‐ and grid‐side converters of PMSG wind generation systems.

For high‐power PMSG‐based wind turbines ranging from 3 MW to 5 MW, parallel‐connected 2‐level LV BTB VSCs are the most cost‐effective converter topology with mature commercial products, particularly for dual 3‐phase stator‐winding PMSG generation systems. For higher‐capacity wind‐turbine driven PMSGs rated from 5 MW to 10 MW, medium voltage multi‐level converters, such as 5‐level regenerative CHB, 3‐ and 4‐level FC BTB VSC, and 3‐level BTB VSC, are preferred. Among them, 3‐level BTB NPC topology is the favorite with well‐proven technology and industrial applications, which can also be extensively applicable with open‐end winding and dual stator‐winding PMSGs so as to create even higher voltage/power wind generation systems. Sensorless control algorithms based on fundamental voltages/currents are suggested to be employed in the basic VC/DPC schemes for enhancing the robustness in the entire PMSG‐based wind power generation system, due to that the problems related with electromagnetic interferences in the position signals and the failures in the mechanical encoders can be avoided.

This second part of the paper for the first time systematically reviews the latest state of arts with regard to power converters and their associated advanced control strategies for high‐power wind energy generation applications. It summarizes a variety of converter topologies with pros and cons highlighted for different power ratings of wind turbines.

This chapter considers how observers can effectively and safely engage with unethical organizational behaviors. Engagement methods need to be aligned with the situational contexts of specific cases. Micro-level individual, meso-level organizational, and macro-level environmental contextual obstacles to effective and safe engagement are considered. Five types of observer ethics engagement methods are considered in the context of specific cases and contextual obstacles. Engagement methods considered are as follows: (1) evocation and framing of dialogic engagement as consistent with the identity, vision, and values of the organization; (2) win–win incentive and ethics networking methods; (3) internal and external whistle-blowing methods; (4) if the observer is in a position of organizational power, top-down forcing methods; and (5) linking of observed unethical behaviors with strong external social movements.

To provide theoretical guidance on improving luxury brands’ marketing performance, this study aims to examine the impact mechanism and boundary conditions of luxury brand buyers’ consumption resources on observers’ brand attitudes from the perspective of consumers’ power distance beliefs (PDBs).

Four experimental studies were conducted. Study 1 examined the influence of the interaction of consumption resources and PDBs on luxury brand attitudes; Study 2 examined the mediating role of prestige perception. Study 3 excluded alternative explanations of (dis)association motivation and envy. Finally, Study 4 examined the moderating effect of brand relationship norms.

Consumers with low PDBs had lower attitudes towards luxury brands when consumption resources were acquired through luck (rather than effort). However, no significant difference in luxury brand attitudes was found between these two consumer groups when PDBs were high. Consumers’ perceptions of prestige played a mediating role in the main effect, whereas brand relationship norms moderated the main effect.

First, this study reveals the unique role of PDBs in shaping consumer attitudes towards luxury brands. Second, it uses consumption resources as a signal for luxury consumption and identifies a way to influence consumers’ attitudes towards luxury brands, namely, their perceptions of prestige. Third, it uncovers the influence of consumers’ brand relationship norms on the formation of luxury brand attitudes.

This work examines the interplay between power, status and style. Building on the dual role of power and status as two primary sources of social influence in contemporary consumer society, we propose that stylistic choices associated with greater status can imbue the wearer with greater feelings of power. We focus on a pervasive stylistic choice for women – whether to wear heels – and test two critical relationships regarding consumers' choice of heels that can act as a bridge between status and power. First, we propose that the stylistic choice of wearing heels increases wearers' perceived status (but not perceived power) – the heeled status-enhancement hypothesis, whereby (1) wearing heels increases wearers' perceived status (but not perceived power) among observers and (2) lacking power (vs having power or baseline) yields greater desire for heels over flats. Second, we propose that an increase in status stemming from wearing heels increases consumers' feelings and behaviours of high power – the status–power transfer hypothesis. Three studies confirm the use and perception of heels as status symbols and provide support for both hypotheses. We show that wearing heels (vs flat shoes) makes individuals feel and behave more powerfully by thinking more abstractly and taking more actions, two hallmarks of high power, but only when heels are worn conspicuously (i.e., the wearer knows the observer sees them). In addition, these effects are mediated by wearer's feelings of power and unexplained by perceptions of sexiness. Implications for the literatures on style, status, power and conspicuous consumption are discussed.

A cascaded observer-based transfer delay frequency locked loop (CODFLL) algorithm is developed to control the distribution static compensator (DSTATCOM) to address various power quality (PQ) issues arise because of distorted grid and load conditions. Moreover, frequency locked loop is included along with the observer to take care of the frequency drift from nominal value and to improve its performance during steady state and transient conditions. During daylight, the proposed system works as photovoltaic (PV) DSTATCOM and performs multiple functions for improving PQ whilst transferring power to grid and load. The system under consideration acts as DSTATCOM during night and bad weather condition to nullify the PQ issues.

CODFLL control algorithm generates reference signal for hysteresis controller. This reference signal is compared with an actual grid signal and a gate pulse is produced for a voltage source converter. The system is made frequency adaptive by transfer delay adaptive frequency locked loop (FLL). Peak power is extracted from a PV source using the perturb and observe technique irrespective of disturbances encountered in the system.

The PV system’s performance with the proposed controller is studied and compared with conventional control algorithms such as least mean fourth (LMF), improved second-order generalized integrator frequency locked loop (ISOGI-FLL), synchronous reference frame phased lock loop (SRF-PLL) and frequency adaptive disturbance observer (DOB) for different cases, for example, steady-state condition, dynamic condition, variable insolation, voltage sag and swell and frequency wandering in the supply side. It is found that the proposed method tracks the frequency variation faster as compared to ISOGI-FLL without any oscillations. During unbalanced loading conditions, CODFLL exhibits zero oscillations. Harmonics in system parameters are reduced to the level of IEEE standard; unity power factor is maintained at the grid side; hassle-free power flow takes place from the source to the grid and load; and consistent voltage profile is maintained at the coupling point.

CODFLL control algorithm is developed for PV-DSTATCOM systems to generate a reference grid current.

This paper aims to propose a novel grid current control strategy for grid-connected voltage source converters (VSCs) under unbalanced grid voltage conditions.

A grid voltage dynamic model is represented in symmetrical positive and negative sequence reference frames. A proportional controller structure with a first-order low-pass filter disturbance observer (DOB) is designed for power control in unbalanced voltage conditions. This controller is capable of meeting the positive sequence power requirements, and it also eliminates negative sequence power components which cause double-frequency oscillations on power. The symmetrical components are calculated by using the second-order generalized integrator-based observer, which accurately estimates the symmetrical components.

Proportional current controllers are sufficient in this study in a wide range of operating conditions, as DOB accurately estimates and feed-forwards nonlinear terms which may be deteriorated by physical and operating conditions. This is the first reported scheme which estimates the VSC disturbances in terms of symmetrical component decomposition and the DOB concept.

The proposed method does not require any grid parameter to be known, as it estimates nonlinear terms with a first-order low-pass filter DOB. The proposed control system is implemented on a dSPACE ds1103 digital controller by using a three-phase, three-wire VSC.

Although supplier-initiated punishment is widely used to manage distributors’ opportunism, its spillover effect on unpunished distributors (i.e. observers) within the same distribution network remains under-researched. Specifically, this paper aims to investigate the curvilinear effect of punishment severity on an observer’s opportunism, and how such an effect is contingent on the observer’s network position.

This paper uses regression analysis with survey data gathered from 218 distributors in China’s automobile industry.

Punishment severity has an inverted U-shaped effect on the observers’ opportunism, and such effect is weakened by both the observers’ network centrality and their degree of dependence on the supplier.

The findings should encourage suppliers to focus more on the spillover effects of punishment on observers. To this end, the supplier must deliberately initiate the appropriate level of punishment severity against its distributors because an inappropriate level of punishment severity (e.g. too lenient) may unexpectedly raise the unpunished observers’ level of opportunism. Moreover, the supplier should be fully aware that observers’ specific network positions may produce varying spillover effects of the punishment.

This study enriches the literature on channel governance by revealing the curvilinear mechanism through which punishment severity influences observers’ opportunism. By applying social learning theory to channel punishment research, this study unveils both the inhibitive learning and the imitative learning forces inherent in a single punishment event, and it delineates their joint effect on an observer’s opportunism. In addition, this study outlines the observer’s vertical and horizontal relationships within the distribution network and explores their contingent roles in determining the spillover effects of punishment.

Individuals are often stigmatized by virtue of their status on various dimensions and as a consequence, they typically evoke negative cognitions, affect, and emotions among observers. In addition, they are often the targets of both access and treatment discrimination in organizations. Thus, we present a model of the cognitive, affective, and cultural influences on stigmatization in organizations, detail how stigmatization affects human resource management processes and practices, and consider strategies that can be used to reduce the problems faced by stigmatized individuals in organizations.