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Article
Publication date: 4 June 2021

Gulay Unal

Fault detection, isolation and reconfiguration of the flight control system is an important problem to obtain healthy flight. This paper aims to propose an integrated…

Abstract

Purpose

Fault detection, isolation and reconfiguration of the flight control system is an important problem to obtain healthy flight. This paper aims to propose an integrated approach for aircraft fault-tolerant control.

Design/methodology/approach

The integrated structure includes a Kalman filter to obtain without noise, a full order observer for sensor fault detection, a GOS (generalized observer scheme) for sensor fault isolation and a fuzzy controller to reconfigure of the healthy sensor. This combination is simulated using the state space model of a lateral flight control system in case of disturbance and under sensor fault scenario.

Findings

Using a dedicated observer scheme, the detection and time of sensor fault are correct, but the sensor fault isolation is evaluated incorrectly while the faulty sensor is isolated correctly using GOS. The simulation results show that the suggested approach works affectively for sensor faults with disturbance.

Originality/value

This paper proposes an integrated approach for aircraft fault-tolerant control. Under this framework, three units are designed, one is Kalman filter for filtering and the other is GOS for sensor fault isolation and another is fuzzy logic for reconfiguration. An integrated approach is sensitive to faults that have disturbances. The simulation results show the proposed integrated approach can be used for any linear system.

Details

Aircraft Engineering and Aerospace Technology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1748-8842

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Book part
Publication date: 2 June 2015

Matthew R. Leon and Jonathon R. B. Halbesleben

One particular egregious type of workplace mistreatment is supervisor abuse, which has received extensive attention due to its heavy cost to organizations including up to…

Abstract

One particular egregious type of workplace mistreatment is supervisor abuse, which has received extensive attention due to its heavy cost to organizations including up to 23 billion dollars in annual loss resulting from increases in absenteeism, health care costs, and productivity loss. Employees attribute causes to abusive supervision, and these attributions impact subsequent reactions. In some cases, employees may feel that abusive supervision is justified, leading to the reaction of Schadenfreude, or pleasure in another’s pain. In this chapter, we discuss antecedents to Schadenfreude, its role in observed mistreatment, and propose a conceptual model based on attribution theory.

Details

Mistreatment in Organizations
Type: Book
ISBN: 978-1-78560-117-0

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Book part
Publication date: 1 January 2005

Mesut Uyar

Peace support operations and the role of the United Nations is getting important in changing the global power system. But generally peace support missions are creating new…

Abstract

Peace support operations and the role of the United Nations is getting important in changing the global power system. But generally peace support missions are creating new problems while trying to solve the original ones. In this presentation I will try to examine the relative effectiveness of the UN in the military observer missions, which is the most common type of UN peace support operations. The UN Observer Mission in Georgia (UNOMIG) is used to show their relative effectiveness in the current world system by means of differentiating the problems they are facing. After showing the common problems, I will give special emphasis to the genuine problems of UNOMIG. First of all we have to take a brief look at the origins of military observer missions. During the long Cold War, the UN had to engage in conflict resolution/management in a world widely divided between two superpowers. The Security Council (SC) suffered lots of problems to handle conflicts without jeopardising the interests of the superpowers. So in most of the cases (except Korea and Congo) the SC did not authorise the necessary military forces to the conflict areas. Instead the SC preferred to send interpositional forces with light arms or military observers without arms after getting the consent of the conflicting parties. Currently we are calling this approach traditional peacekeeping. By experiences gained on the ground and in the SC it was understood that the best and easiest reaction is establishing a UN military observer mission (UNMOM) (Mackinlay, 1996, pp. 9–11; British Army, 1995, pp. 1–2/2–7). According to this limited and conservative logic this process must follow standard steps: First an armed conflict between two states; second a stalemate that nobody is able to defeat the other side completely; third conflicting states ask the UN to enforce a ceasefire; fourth the SC authorises neutral military observers to monitor a ceasefire and to achieve some other limited objectives, according their mandate; fifth conflicting states try to reach a peaceful solution by diplomatic negotiations with the help of the UN; sixth agreement is reached and end of UNMOM. In short, the duty of the military observers is to monitor the ceasefire and the restrictions agreed to by both parties in a geographically limited area for a limited time. But in reality, diplomatic negotiations often do not provide fast and lasting solutions. UNMOMs have remained and temporary missions turned into permanent ones. The answer to the question why is that they are economically cheap operations and politically easier to maintain than to remove. Most of the UNMOMs that were established in different continents are still going on without an end in sight (Brahimi et al., 2000, p. 3).

Details

Military Missions and their Implications Reconsidered: The Aftermath of September 11th
Type: Book
ISBN: 978-1-84950-012-8

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Book part
Publication date: 15 July 2009

Ella Miron-Spektor and Anat Rafaeli

Most anger research has adopted a within-person view, focusing on the effects of experienced anger on a person's feelings, cognition, and behavior. Less research has…

Abstract

Most anger research has adopted a within-person view, focusing on the effects of experienced anger on a person's feelings, cognition, and behavior. Less research has examined the effects of anger expressed by one person on other people in the workplace. We review available literature on the interpersonal effects of anger and propose a theoretical framework that addresses two main questions (1) What mechanisms can explain the effects of observed anger on other people? and (2) What factors may strengthen or attenuate these effects? We propose that observed anger affects observers’ performance via emotional and cognitive routes that are interrelated, and that this effect depends on the properties of the expressed anger, the situation in which the anger occurs, and the task being performed by the observer.

Details

Research in Personnel and Human Resources Management
Type: Book
ISBN: 978-1-84855-056-8

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Article
Publication date: 3 April 2020

Marjan Abbasi

The purpose of this paper is to investigate the effect of complete versus partial observations of service failure and recovery. This study also aims at investigating the…

Abstract

Purpose

The purpose of this paper is to investigate the effect of complete versus partial observations of service failure and recovery. This study also aims at investigating the effect of observing customers’ need for cognitive closure and types of compensation that a service provider offers.

Design/methodology/approach

Two experiments are conducted to test the research hypotheses. The authors use scenarios describing failure and recovery encounters that occur to a target customer at restaurant settings, and through manipulation of complete versus partial observations, they investigate observers’ attitudes and behavioral intentions.

Findings

The results suggest that customers with a partial observation are less forgiving than those with a complete observation. In particular, the former sympathized more with a target customer, blamed a service provider more and a target customer less and had lower repurchase intentions than the latter. The authors find that the need for cognitive closure heightens this tendency following a partial observation of service failure. They also find that following a complete (versus partial) observation, observers reacted more favorably to service recovery when it included (versus did not include) monetary compensation.

Research limitations/implications

This research studies the effect of locus of causality following a partial versus complete observation. Future research could further examine the effect of stability and controllability. Also, the authors examined the effect of the need for cognitive closure on evaluations of service failure following a partial versus complete observation. Future research could examine the effect of some other individual difference variables.

Practical implications

The results offer some measures to be taken by practitioners. In particular, practitioners are advised to not offer monetary compensation when majority of observers have had a partial observation. Moreover, they are advised to offer some explanation in a timely and effective manner to ensure observers who are under the negative impact of a partial observation have some information so that they revisit their service evaluations.

Originality/value

The literature assumes that in failure and recovery incidents, all observing customers would know the entire story. This research challenges this assumption and highlights the key role of observation type (partial versus complete observation). Further, this research examines the effect of the need for cognitive closure on service evaluations following a partial versus complete observation. The current research finds that supposedly favorable measures by a firm (i.e. monetary compensation) may in fact backfire when a partial observation is at play.

Details

European Journal of Marketing, vol. 54 no. 4
Type: Research Article
ISSN: 0309-0566

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Article
Publication date: 16 December 2019

Andrei Cretu

W. Ross Ashby’s elementary non-trivial machine, known in the cybernetic literature as the “Ashby Box,” has been described as the prototypical example of a black box…

Abstract

Purpose

W. Ross Ashby’s elementary non-trivial machine, known in the cybernetic literature as the “Ashby Box,” has been described as the prototypical example of a black box system. As far as it can be ascertained from Ashby’s journal, the intended purpose of this device may have been to exemplify the environment where an “artificial brain” may operate. This paper describes the construction of an elementary observer/controller for the class of systems exemplified by the Ashby Box – variable structure black box systems with parallel input.

Design/methodology/approach

Starting from a formalization of the second-order assumptions implicit in the design of the Ashby Box, the observer/controller system is synthesized from the ground up, in a strictly system-theoretic setting, without recourse to disciplinary metaphors or current theories of learning and cognition, based mainly on guidance from Heinz von Foerster’s theory of self-organizing systems and W. Ross Ashby’s own insights into adaptive systems.

Findings

Achieving and maintaining control of the Ashby Box requires a non-trivial observer system able to use the results of its interactions with the non-trivial machine to autonomously construct, deconstruct and reconstruct its own function. The algorithm and the dynamical model of the Ashby Box observer developed in this paper define the basic specifications of a general purpose, unsupervised learning architecture able to accomplish this task.

Originality/value

The problem exemplified by the Ashby Box is fundamental and goes to the roots of cybernetic theory; second-order cybernetics offers an adequate foundation for the mathematical modeling of this problem.

Details

Kybernetes, vol. 49 no. 8
Type: Research Article
ISSN: 0368-492X

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Article
Publication date: 17 April 2020

Shahin Sharifi and Gerri Spassova

The purpose of this paper is to investigate the effect of interdependent vs independent self-construal on service satisfaction, following the observation of failure and…

Abstract

Purpose

The purpose of this paper is to investigate the effect of interdependent vs independent self-construal on service satisfaction, following the observation of failure and recovery experienced by a fellow customer.

Design/methodology/approach

Three experiments were conducted to test the research hypotheses.

Findings

After service failure, interdependent observers react less favorably compared to independent observers. After high recovery compensation, interdependent observers react more favorably compared to independent observers. The effects are driven by differences in perceived interactional and distributive justice.

Research limitations/implications

This study uses three scenario-based experiments to test the hypotheses. While providing greater control of the experimental conditions, the external validity of the results is to some extent sacrificed. Moreover, this research does not investigate observers’ reactions to the interactional aspect of recovery.

Practical implications

When handling service failure, firms are required to anticipate and address not only the responses of the target customers involved but also those of potential observers. Providers can accordingly use available customer information to gauge customers’ likely self-construal and to adjust their service delivery and recovery tactics. Providers can influence observing customers’ reactions by creating a servicescape that activates a desired self-construal.

Originality/value

This research is one of a few to examine the effect of service failure and recovery on observing customers, and the first to do so via the lens of self-construal. It contributes to the literature on service failure and recovery and the literature on self-construal and has practical implications for service providers. The value of this research is further highlighted given the increasingly public nature of services and the multicultural context of service delivery.

Details

European Journal of Marketing, vol. 54 no. 5
Type: Research Article
ISSN: 0309-0566

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Article
Publication date: 1 December 2004

Konrad Urbański and Krzysztof Zawirski

This paper deals with the problem of rotor speed and position detection in sensorless permanent magnet synchronous motor (PMSM) drives. A concept based on detecting the…

Abstract

This paper deals with the problem of rotor speed and position detection in sensorless permanent magnet synchronous motor (PMSM) drives. A concept based on detecting the back EMF induced in stator windings was developed and modified. A general structure of an adaptive observer with the proportional‐integral function of a corrector is introduced. The non‐stationary character of the observer presented in this paper requires an adaptive change of observer corrector settings. Such observer structure was implemented on a DSP system and verified experimentally. Both simulation and experimental results show good properties of the proposed observer structure.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 23 no. 4
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 31 May 2013

Mejda Mansouri, Latifa Boutat‐Baddas, Mohamed Darouach and Hassani Messaoud

The purpose of this paper is to propose a decentralized observer for large‐scale singular systems.

Abstract

Purpose

The purpose of this paper is to propose a decentralized observer for large‐scale singular systems.

Design/methodology/approach

In this paper, the authors investigate the problem of observers' design for large‐scale singular systems. The proposed decentralized observer is based on a new parameterization of the generalized Sylvester equation solution. The considered system is partitioned into small‐sizes interconnected subsystems with unknown interconnections.

Findings

A decentralized observer based on new parameterization of generalized Sylvester equation. The performance of the proposed approach is illustrated by a numerical example.

Originality/value

The proposed approach unites the full‐order, the reduced‐order and the minimal order observer design for large‐scale system. The conditions of the existence of this observer are given in the linear matrix inequalities (LMI) form.

Details

International Journal of Intelligent Computing and Cybernetics, vol. 6 no. 2
Type: Research Article
ISSN: 1756-378X

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Article
Publication date: 1 January 2005

Humberto Maturana Romesín

To reflect on the matter of self‐consciousness.

Abstract

Purpose

To reflect on the matter of self‐consciousness.

Design/methodology/approach

The purpose is achieved through the process of answering four questions presented to me by Heinz von Foerster in the course of our many conversations.

Findings

It is not possible to understand the nature of self‐consciousness without understanding the operation of human beings as living systems that exist as emotional languaging living systems: self‐consciousness is a manner of living.

Practical implications

We human beings can become more aware of our responsibility in the design of robots that imitate us.

Originality/value

Reflects on what makes us humans special, on subjective experience, and on the world we bring forth.

Details

Kybernetes, vol. 34 no. 1/2
Type: Research Article
ISSN: 0368-492X

Keywords

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