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The purpose of this paper is to propose an adaptive neural-sliding mode-based observer for the estimation and reconstruction of unknown faults and disturbances for time-varying nonlinear systems such as aircraft, to ensure preciseness in the diagnosis of fault magnitude as well as the shape without enhancement of system complexity and cost. Fault-tolerant control (FTC) strategy based on adaptive neural-sliding mode is also proposed in the existence of faults for ensuring the stability of the faulty system.

In this paper, three strategies are presented: adaptive radial basis functions neural network (ARBFNN), conventional radial basis functions neural network (CRBFNN) and integral-chain differentiator. For the purpose of enhancement of fault diagnosis and isolation, a new sliding mode-based concept is introduced for the weight updating parameters of radial basis functions neural network (RBFNN).The main objective of updating the weight parameters adaptively is to enhance the effectiveness of fault diagnosis and isolation without increasing the computational complexities of the system. Results depict the effectiveness of the proposed ARBFNN approach in fault detection (FD) and approximation compared to CRBFNN, integral-chain differentiator and schemes existing in literature. In the second step, the FTC strategy is presented separately for each observer in the presence of unknown faults and failures for ensuring the stability of the system, which is validated on Boeing 747 100/200 aircraft.

The proposed adaptive neural-sliding mode approach is investigated, which depicts more effectiveness in numerous situations such as faults, disturbances and uncertainties compared to algorithms used in literature. In this paper, both the fault approximation and isolation and the fault tolerance approaches are studied.

For the enhancement of safety level as well as for avoiding any kind of damage, timely FD and fault tolerance have always had a significant role; therefore, the algorithms proposed in this research ensure the tolerance of faults and failures, which plays a vital role in practical life for avoiding any kind of damage.

In this study, a new neural-sliding mode concept is adopted for the adaptive faults approximation and reconstruction, and then the FTC algorithms are studied for each observer separately, whereas in previous studies, only the fault detection and isolation (FDI) or the fault tolerance problems were studied. Results demonstrate the effectiveness of the proposed strategy compared to the approaches given in the literature.

This article aims to examine the US history of practices that mask the marketing content of messages to consumers and of the public policy approaches taken towards such practices.

This research examines both primary sources such as legal challenges and contemporary writings as well as secondary sources.

The US legal/regulatory system has been examining practices that mask the marketing content of communications for over 125 years. Fully masked messages were initially regulated under postal service laws and publisher self‐regulatory codes. Partially masked messages, e.g. testimonials, were examined first by courts and later by regulatory and industry self‐regulatory agencies. These diverse sources of regulation led to diverse approaches and in part explain the modern preference for information disclosure over prohibiting the masking of marketing messages.

Modern analysis of these practices ignores their history and the historical evolution of their regulation. This article not only reveals a rich regulatory history, but also suggests that modern policy should treat the broad array of masking practices consistently and correct current policy approaches that are based on historical development rather than modern public policy analysis and concerns.

The purpose of this paper is to estimate the impact of fixed-term contracts (FTCs) on labour productivity, wages (i.e. labour cost), and productivity-wage gaps (i.e. profits).

The authors apply dynamic panel data techniques to detailed Belgian linked employer-employee panel data covering the period 1999-2006.

Results indicate that FTCs exert stronger positive effects on productivity than on wages and (accordingly) that the use of FTCs increases firms’ profitability.

This paper is one of the first to examine the FTC-productivity-wage nexus while addressing three important methodological issues related to the state dependency of the three explained variables, to firm time-invariant heterogeneity, and to the endogeneity of FTCs.

This paper aims to propose a multi-scale simulation approach for the concrete macro-mechanical damage caused by mixed micro-pore pressures, such as the coupled alkali–silica reaction (ASR) and freeze-thaw cycles (FTC).

The micro-physical events are computationally modeled by considering the coupling effect between ASR gel and condensed water in the mixed pressure and motion. The pressures and transport of pore substances are also linked with the concrete matrix deformation at macro-scale through a poro-mechanical approach, and affect each other, reciprocally. Once the crack happens in the nonlinear analysis, both the micro-events (water and gel motion) and the macro mechanics will be mutually interacted. Finally, different sequences of combined ASR and FTC are simulated.

The multi-chemo mechanistic computation can reproduce complex events in pore structures, and further the macro-damages. The results show that ASR can reduce the FTC expansion for non-air-entrained concrete, but may increase the frost damage for air-entrained concrete. The simulation is examined to bring about the observed phenomena.

This paper numerically clarifies the strong linkage between macro-mechanical deformation and micro-chemo-physical events for concrete composites under coupled ASR and FTC.

There are high expectations for reliability, safety and fault tolerance are high in chemical plants. Control systems are capable of potential faults in the plant processing systems. This paper proposes is a new Fault Tolerant Control (FTC) system to identify the probable fault occurrences in the plant.

A Fault Diagnosis and Isolation (FDI) module has been devised based on the estimated state of system. An Unscented Kalman Filter (UKF) is the main innovation of the FDI module to identify the faults. A Multi-Sensor Data Fusion algorithm is utilized to integrate the UKF output data to enhance fault identification. The UKF employs an augmented state vector to estimate system states and faults simultaneously. A control mechanism is designed to compensate for the undesirable effects of the detected faults.

The performance of the Nonlinear Model Predictive Controller (NMPC) without any fault compensation is compared with the proposed FTC scheme under different fault scenarios. Analysis of the simulation results indicates that the FDI method is able to identify the faults accurately. The proposed FTC approach facilitates recovery of the closed loop performance after the faults have been isolated.

A significant contribution of the paper is the design of an FTC system by using UKF to estimate faults and enhance the accuracy of data. This is done by applying a data fusion algorithm and controlling the system by the NMPC after eliminating the effects of faults.

The purpose of this paper is to investigate the impact of key labor institutions on the occurrence and extent of temporary employment.

In a new departure, this study uses a zero-inflated negative binomial (ZINB) model given that most establishments are non-users of either fixed-term contracts (FTCs) or temporary agency workers.

This study examines the potential impact of works councils and unions on the use and intensity of use of FTCs and temporary agency work. There is a little indication that these variables are correlated with the use/non-use of either type of temporary work, especially in the case of FTCs. Collective bargaining displays different relationships with their intensity of use: a negative association for sectoral bargaining and FTCs and the converse for firm-level bargaining and agency temps. Of more interest, however, is the covariation between the number of temporary employees and the interaction between works councils and product market volatility. The intensity of use of agency temps (FTCs) is predicted to rise (fall) as volatility increases whenever a works council is present. These disparities require further investigation but most likely reflect differences in function, with agency work being more directed toward the protection of an arguably shrinking core and fixed-term contacts encountering resistance to their increased use as a buffer stock. The two types of temporary employment are seemingly non-complementary, an interpretation that receives support from the study’s further analysis of FTC flow data.

The non-complementarity of the two types of contract is the hallmark of this paper.

The first study to deploy a ZINB model to examine both the occurrence and incidence of temporary work.

Over the past 30 years the United States has grappled with the regulation of children's advertising in various media. The same debate that occurred in the 1970's in the US over banning children's advertising is heating up in the EU today. As with other regulatory issues the regulation of children's advertising involves trade‐offs. In the US, the First Amendment rights of the advertisers must be balanced with the government interest in protecting children. The regulation of children's advertising also involves balancing the competing interests of advocacy groups, legislators, broadcasters and advertisers. Advocacy groups have been very effective in focusing public attention on the issues of children's advertising. One of the most vocal and impactful groups was Action for Children's Television (ACT), whose efforts culminated in the passage of the 1990 Children's Television Act. Once that was accomplished, ACT was disbanded. In more recent years, however, the Centre for Media Education (CME) has replaced ACT in calling for regulation of children's advertising. CME was instrumental in pushing the 1996 FTC investigation related to 900 telephone numbers directed at children, and is now behind the Child Online Protection Act (COPA). The same questions raised nearly 30 years ago by ACT are now being cast in the US in terms of the Internet, otherwise little has changed. Each new innovation in media and technology ushers similar questions to the table, and the same balancing act must again be employed to answer the basic question: how far do we go to protect our children? The US's answer to this question offers insights for other countries seeking answers to similar questions.

This paper aims to focus on the sensor fault-tolerant control (FTC) for civil aircraft under exterior disturbance.

First, a three-step cubature Kalman filter (TSCKF) is designed to detect and isolate the sensor fault and to reconstruct the sensor signal. Meanwhile, a nonlinear disturbance observer (NDO) is designed for disturbance estimation. The NDO and the TSCKF are combined together and an NDO-TSCKF is proposed to solve the problem of sensor faults and bounded disturbances simultaneously. Furthermore, an FTC scheme is designed based on the nonlinear dynamic inversion (NDI) and the NDO-TSCKF.

The method is verified by a Cessna 172 aircraft model under bias gyro fault and constant angular rate disturbance. The proposed NDO-TSCKF has the ability of signal reconstruction and disturbance estimation. The proposed FTC scheme is also able to solve the sensor fault and disturbance simultaneously.

NDO-TSCKF is the novel algorithm used in sensor signal reconstruction for aircraft. Then, disturbance observer-based FTC can improve the flight control system performances when the system with faults.

The NDO-TSCKF-based FTC scheme can be used to solve the sensor fault and exterior disturbance in flight control. For example, the bias gyro fault with constant angular rate disturbance of a civil aircraft is studied.

Signal reconstruction for critical sensor faults and disturbance observer-based FTC for civil aircraft are useful in modern civil aircraft design and development.

This is the research paper studies on the signal reconstruction and FTC scheme for civil aircraft. The proposed NDO-TSCKF is better than the current reconstruction filter because the failed sensor signal can be reconstructed under disturbances. This control scheme has a better fault-tolerant capability for sensor faults and bounded disturbances than using regular NDI control.

The purpose of this paper is to look at the problem of fault tolerant control (FTC) for discrete time nonlinear system described by Interval Type-2 Takagi–Sugeno (IT2 TS) fuzzy model subjected to stochastic noise and actuator faults.

An IT2 fuzzy augmented state observer is first developed to estimate simultaneously the system states and the actuator faults since this estimation is required for the design of the FTC control law. Furthermore, based on the information of the states and the faults estimate, an IT2 fuzzy state feedback controller is conceived to compensate for the faults effect and to ensure a good tracking performance between the healthy system and the faulty one. Sufficient conditions for the existence of the IT2 fuzzy controller and the IT2 fuzzy observer are given in terms of linear matrix inequalities which can be solved using a two-step computing procedure.

The paper opted for simulation results which are applied to the three-tank system. These results are presented to illustrate the effectiveness of the proposed FTC strategy.

In this paper, the problem of active FTC design for noisy and faulty nonlinear system represented by IT2 TS fuzzy model is treated. The developed IT2 fuzzy fault tolerant controller is designed such that it can guarantee the stability of the closed-loop system. Moreover, the proposed controller allows to accommodate for faults, presents a satisfactory state tracking performance and outperforms the traditional type-1 fuzzy fault tolerant controller.