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Steer-by-wire (SBW) system mainly relies on sensors, controllers and motors to replace the traditionally mechanical transmission mechanism to realize steering functions. However, the sensors in the SBW system are particularly vulnerable to external influences, which can cause systemic faults, leading to poor steering performance and even system instability. Therefore, this paper aims to adopt a fault-tolerant control method to solve the safety problem of the SBW system caused by sensors failure.

This paper proposes an active fault-tolerant control framework to deal with sensors failure in the SBW system by hierarchically introducing fault observer, fault estimator, fault reconstructor. Firstly, the fault observer is used to obtain the observation output of the SBW system and then obtain the residual between the observation output and the SBW system output. And then judge whether the SBW system fails according to the residual. Secondly, dependent on the residual obtained by the fault observer, a fault estimator is designed using bounded real lemma and regional pole configuration to estimate the amplitude and time-varying characteristics of the faulty sensor. Eventually, a fault reconstructor is designed based on the estimation value of sensors fault obtained by the fault estimator and SBW system output to tolerate the faulty sensor.

The numerical analysis shows that the fault observer can be rapidly activated to detect the fault while the sensors fault occurs. Moreover, the estimation accuracy of the fault estimator can reach to 98%, and the fault reconstructor can make the faulty SBW system to retain the steering characteristics, comparing to those of the fault-free SBW system. In addition, it was verified for the feasibility and effectiveness of the proposed control framework.

As the SBW fault diagnosis and fault-tolerant control in this paper only carry out numerical simulation research on sensors faults in matrix and laboratory/Simulink, the subsequent hardware in the loop test is needed for further verification.

Aiming at the SBW system with parameter perturbation and sensors failure, this paper proposes an active fault-tolerant control framework, which integrates fault observer, fault estimator and fault reconstructor so that the steering performance of SBW system with sensors faults is basically consistent with that of the fault-free SBW system.

This paper aims to investigate the ways in which “non-collaborative co-creation” can affect brand equity as perceived by independent observers. It reports a study of the different effects on that perception attributable to non-collaborative co-creation that takes the form of either “brand play” or “brand attack” and is executed either by established artists or mainstream consumers.

A 2 × 2 between-subjects experiment (brand play versus brand attack; consumer versus artist) measured observers’ perception of brand equity before and after exposure to purpose-designed co-created treatments.

Non-collaborative co-creation has a negative effect on observers’ perceptions of brand equity and brand attack, causing a stronger dilution of brand equity than brand play. Artists either mitigate the dilution or have a positive effect on those perceptions.

Future research could usefully investigate the relative susceptibility of brands to non-collaborative co-creation, the effects on brands of higher complexity than those in our experiment, exposed in higher-involvement media, and the effects of more diverse forms of co-creation.

Brand managers must recognise that co-creation carries considerable risks for brand equity. They should closely monitor and track the first signs of non-collaborative co-creation in progress. It could be beneficial to recruit artists as co-creators of controlled brand play.

This study offers a more complete insight into the effect of non-collaborative co-creation on observers’ perceptions of brand equity than so far offered by the existing literature. It connects the fields of brand management and the arts by investigating the role and impact of artists as collaborative or non-collaborative co-creators of brand equity.

Most of the studies in entrepreneurship depend on single-source rating methods to collect data on both predictors and criteria. The threat to effect sizes as a result of using single-source ratings is particularly relevant to psychology-based entrepreneurship research. Therefore, the purpose of this paper is to explore the prospects of applying 360-degree feedback to the field of entrepreneurship and to discuss a set of cases regarding how 360-degree feedback may boost effect sizes in entrepreneurship research.

A qualitative review of current literature was performed.

The review indicated that the effect sizes in psychology-based entrepreneurship research are mostly small and the use of single-source ratings is prevalent; some preliminary findings supported the utility of 360-degree feedback in entrepreneurship research; entrepreneurial orientation (EO) research may benefit from 360-degree feedback; and members of top management teams, employees from research and product development, sales agents, retail buying agents, store sales clerks, and consumers are all valid informants to provide ratings of EO.

The present study provided theoretical explanations and used empirical evidence to elucidate how 360-degree feedback may benefit the field of entrepreneurship. In addition, recommendations for future research using 360-degree feedback in entrepreneurship research were offered and discussed. A sample research study on EO using 360-degree feedback was delineated.

This study focused on identifying measurable constructs of a restorative classroom and appropriate metrics to measure those constructs through content validity analysis of a direct observation tool. The tool was designed to assess restorative practices implementation in the classroom in the context of professional development supporting teachers in a fundamental reorientation towards non-punitive discipline.

The authors administered a 30-item survey to a panel of 14 experts in restorative practices implementation in schools asking them to provide quantitative and qualitative feedback on the tool's content, metrics, and utility for building teachers' skill and confidence in promoting a restorative classroom. The authors calculated item-level content validity indices and scale-level content validity indices. To interpret findings, the authors applied acceptability criteria recommended in the literature. The authors used qualitative coding to analyze qualitative responses and contextualize quantitative findings.

Quantitative results indicated that the tool's structure and measures of teacher behavior were acceptable. The student behavior scale did not meet the acceptability criterion. Qualitative feedback indicated that observation and later co-reflection on teachers' use of specific restorative skills was deemed helpful to teacher implementation of restorative practices. Observations of student behaviors, however, needed to be broadened to emphasize student voice and agency and the quality of student interactions.

Novel approaches to measurement are needed to facilitate teacher implementation of restorative practices as schools adopt those practices to promote equitable student agency, engagement and belonging in a pivotal shift from existing punitive discipline systems.

The flexibility of batch process enables its wide application in fine-chemical, pharmaceutical and semi-conductor industries, whilst its complexity necessitates control performance monitoring to ensure high operation efficiency. This paper proposes a data-driven approach to carry out controller performance monitoring within batch based on linear quadratic Gaussian (LQG) method.

A linear time-varying LQG method is proposed to obtain the joint covariance benchmark for the stochastic part of batch process input/output. From historical golden operation batch, linear time-varying (LTV) system and noise models are identified based on generalized observer Markov parameters realization.

Open/closed loop input and output data are applied to identify the process model as well as the disturbance model, both in Markov parameter form. Then the optimal covariance of joint input and output can be obtained by the LQG method. The Hotelling's Tˆ2 control chart can be established to monitor the controller.

(1) An observer Markov parameter approach to identify the time-varying process and noise models from both open and closed loop data, (2) a linear time-varying LQG optimal control law to obtain the optimal benchmark covariance of joint input and output and (3) a joint input and output multivariate control chart based on Hotelling's T² statistic for controller performance monitoring.

The purpose of this paper is to investigate the design method of partial observer canonical form (POCF), which is one of the important research tools for industrial plants.

Motivated by the two-steps method proposed in Xu et al. (2020), this paper extends this method to the case of Multi-Input Multi-Output (MIMO) nonlinear system. It decomposes the original system into two subsystems by observable decomposition theorem first and then transforms the observable subsystem into OCF. Furthermore, the necessary and sufficient conditions for the existing of POCF are proved.

The proposed method has a wide range of applications including completely observable nonlinear system, noncompletely observable nonlinear system, autonomous nonlinear system and forced nonlinear system. Besides, comparing to the existing results (Saadi et al., 2016), the method requires less verified conditions.

The new method concerning design POCF has better plants compatibility and less validation conditions.

Since public sector organizations provide services to citizens but struggle with poor perceptions of their functioning, it is valuable to examine how their online responses to complaints on social media could impact their reputation. Yet, surprisingly little is known about effects of public organizations' webcare. Therefore, this study assesses the impact of the webcare's tone, response strategy and user's involvement on participants’ continuance intention and perceptions of reputation.

Two experimental studies (Study 1: N = 424; Study 2: N = 203) with an interval of one week were carried out to assess the effects of singular and repeated exposure to webcare by a Dutch public transport organization on the participants' continuance intention and perceived organizational reputation. Study 1 examined the effects of the webcare's tone (corporate vs conversational human voice (CHV)) and response strategy (accommodative vs defensive); Study 2 contained tone of voice and user's involvement (observer vs complainer). The effects of repeated exposure to the webcare's tone were also examined.

The results indicate that perceptions of CHV in webcare contribute to webcare as reputation management tool, since it leads to immediate higher reputation scores that also remain stable after repeated exposure. Furthermore, people's continuance intention increased after repeated exposure to webcare responses that were perceived as CHV, thus a natural and engaging communication style, indicating this is an effective strategy for customer care as well. No substantial impact was found for response strategy and user's involvement in the complaint handling.

The novelty of this study is that the authors assess the effects of the webcare's tone combined with response strategy and user's involvement in a public sector context with a sector-specific conceptualization of reputation and continuance intention measured after singular and repeated exposure to webcare.

The purpose of this paper is to carry out a review of the academic literature about corporate social irresponsibility (CSIR) highlighting aspects that help us to define socially irresponsible behaviour and its relationship with socially responsible behaviour.

Through a Boolean search of studies related to terms of irresponsibility undertaken from 1956 to October 2016, the authors develop a review of the literature focussing on the main perspectives used for defining the term of CSIR.

The paper provides a framework of three main dimensions for understanding the differences in the literature that defines CSIR: who defines irresponsible behaviour, an impartial observer or a specific group of stakeholders, whether it is a firm strategy or a punctual action and which is the relationship between corporate social responsibility (CSR) and CSIR, continuity vs orthogonal relationship.

The paper provides and extensive and original review of a key construct, CSIR, and develops some insights about its antecedents and consequences. The authors try to provide light to the contradictory situation where a growing interest in CSR and the increase in voluntary commitments adopted by company leaders incorporating CSR into their strategies are, paradoxically, increasingly associated with CSIR.

In recent years, owing to the rapidly increasing labor costs, the demand for robots in daily services and industrial operations has been increased significantly. For further applications and human–robot interaction in an unstructured open environment, fast and accurate tracking and strong disturbance rejection ability are required. However, utilizing a conventional controller can make it difficult for the robot to meet these demands, and when a robot is required to perform at a high-speed and large range of motion, conventional controllers may not perform effectively or even lead to the instability.

The main idea is to develop the control law by combining the SMC feedback with the ADRC control architecture to improve the robustness and control quality of a conventional SMC controller. The problem is formulated and solved in the framework of ADRC. For better estimation and control performance, a generalized proportional integral observer (GPIO) technique is employed to estimate and compensate for unmodeled dynamics and other unknown time-varying disturbances. And benefiting from the usage of GPIO, a new SMC law can be designed by synthesizing the estimation and its history.

The employed methodology introduced a significant improvement in handling the uncertainties of the system parameters without compromising the nominal system control quality and intuitiveness of the conventional ADRC design. First, the proposed method combines the advantages of the ADRC and SMC method, which achieved the best tracking performance among these controllers. Second, the proposed controller is sufficiently robust to various disturbances and results in smaller tracking errors. Third, the proposed control method is insensitive to control parameters which indicates a good application potential.

High-performance robot tracking control is the basis for further robot applications in open environments and human–robot interfaces, which require high tracking accuracy and strong disturbance rejection. However, both the varied dynamics of the system and rapidly changing nonlinear coupling characteristic significantly increase the control difficulty. The proposed method gives a new replacement of PID controller in robot systems, which does not require an accurate dynamic system model, is insensitive to control parameters and can perform promisingly for response rapidity and steady-state accuracy, as well as in the presence of strong unknown disturbances.

This study aims to examine humans’ reactions to service robots’ display of warmth in robot-to-robot interactions – a setting in which humans’ impressions of a service robot will not only be based on what this robot does in relation to humans, but also on what it does to other robots.

Service robot display of warmth was manipulated in an experimental setting in such a way that a service robot A expressed low versus high levels of warmth in relation to another service robot B.

The results indicate that a high level of warmth expressed by robot A vis-à-vis robot B boosted humans’ overall evaluations of A, and that this influence was mediated by the perceived humanness and the perceived happiness of A.

Numerous studies have examined humans’ reactions when they interact with a service robot or other synthetic agents that provide service. Future service encounters, however, will comprise also multi-robot systems, which means that there will be many opportunities for humans to be exposed to robot-to-robot interactions. Yet, this setting has hitherto rarely been examined in the service literature.