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To solve the above problems and ensure the stability of the ad hoc network node topology in the process of wireless signal transmission, this paper aims to design a robust adaptive sliding film fault-tolerant controller under the nonlinear distortion of signal transmission in an amorphous flat air-to-ground wireless ad hoc network system.

This paper designs a robust adaptive sliding film fault-tolerant controller under the nonlinear distortion of signal transmission in an amorphous flat air-to-ground wireless ad hoc network system.

The simulation results show that the amorphous flat wireless self-organizing network system has good nonlinear distortion fault-tolerant correction ability under the feedback control of the designed controller, and the system has the asymptotically stable convergence ability; the test results show: the node topology of the self-organizing network structural stability is significantly improved, which provides a foundation for the subsequent realization of long-distance transmission of ad hoc network nodes.

Because of the chosen research approach, the research results may lack generalizability. Therefore, researchers are encouraged to test the proposed propositions further.

The controller can extract the fault information caused by nonlinear distortion in the wireless signal transmission process, and at the same time, its feedback matrix K can gradually converge the generated wireless signal error to zero, to realize the stable transmission of the wireless signal.

In this paper, the authors take an amorphous flattened air-ground wireless self-assembling network system as the research object and focus on solving the wireless self-assembling network topology instability problem caused by unknown control communication faults during the operation of this system.

In the paper, the authors propose a neural network-based direct robust adaptive non-fragile fault-tolerant control algorithm suitable for the air-ground integrated wireless ad hoc network integrated system.

The simulation results show that the system eventually tends to be asymptotically stable, and the estimation error asymptotically tends to zero with the feedback adjustment of the designed controller. The system as a whole has good fault tolerance performance and autonomous learning approximation performance. The experimental results show that the wireless self-assembled network topology has good stability performance and can change flexibly and adaptively with scene changes. The stability performance of the wireless self-assembled network topology is improved by 66.7% at maximum.

The research results may lack generalisability because of the chosen research approach. Therefore, researchers are encouraged to test the proposed propositions further.

This paper designs a direct, robust, non-fragile adaptive neural network fault-tolerant controller based on the Lyapunov stability principle and neural network learning capability. By directly optimizing the feedback matrix K to approximate the robust fault-tolerant correction factor, the neural network adaptive adjustment factor enables the system as a whole to resist unknown control and communication failures during operation, thus achieving the goal of stable wireless self-assembled network topology.

The paper takes the air-ground integrated wireless ad hoc network-integrated system as the research object, this paper aims to propose a distributed robust H_∞ adaptive fault-tolerant control algorithm suitable for the system to distribute to solve the problem of control and communication failure at the same time.

In the paper, the authors propose a distributed robust H_∞ adaptive fault-tolerant control algorithm suitable for the air-ground integrated wireless ad hoc network-integrated system.

The results show that the integrated system has good robustness and fault tolerance performance indicators for flight control and wireless signal transmission when confronted with external disturbances, internal actuator failures and wireless network associated failures and the flight control curve of the quadrotor unmanned aerial vehicle (UAV) is generally smooth and stable, even if it encounters external disturbances and actuator failures, its fault tolerance performance is very good. Then in the range of 400–800 m wireless communication distance, the success rate of wireless signal loop transmission is stable at 80%–100% and the performance is at least relatively improved by 158.823%.

This paper takes the air-ground integrated wireless ad hoc network-integrated system as the research object, based on the robust fault-tolerant control algorithm, the authors propose a distributed robust H_∞ adaptive fault-tolerant control algorithm suitable for the system and through the Riccati equation and linear matrix inequation method, the designed distributed robust H_∞ adaptive fault-tolerant controller further optimizes the fault suppression factor γ, so as to break through the limitation of only one Lyapunov matrix for different fault modes to distribute to solve the problem of control and communication failure at the same time.

The purpose of this paper is to present improvements in X‐ray equipment, which are leading to wider use.

Developments in X‐ray sources and detectors are described. This is followed by a review of the more innovative equipment available for security and industrial applications.

Technological developments have produced smaller, lighter X‐ray systems and extended their applications to on‐site work. Multiple wavelength systems distinguish between different materials, and stereo systems remove ambiguities from X‐ray security imaging and allow 3D gauging of industrial components.

The paper highlights the availability of portable X‐ray systems and explains the underlying technology.

The General Industries Division will be featuring a number of new products recently added to its Surcol range of acrylic polymers.

This paper aims to provide an overview of applications of medical rapid prototyping (MRP)-assisted customized surgical guides (CSGs) and shows the potential of this technology in complex surgeries. This review paper also reports two case studies from open literature where MRP-assisted CSGs have been successfully used in complex surgeries.

Key publications from the past two decades have been reviewed.

This study concludes that the use of MRP-assisted CSGs improves the accuracy of surgery. Additionally, MRP-assisted CSGs make the surgery much faster, accurate and cheaper than any other technique. The outcome based on literature review and two case studies strongly suggested that MRP-assisted CSGs might become part of a standard protocol in the medical sector to operate the various complex surgeries, in the near future.

Advanced technologies like radiology, image processing, virtual surgical planning (VSP), computer-aided design (CAD) and MRP made it possible to fabricate the CSGs. MRP-assisted CSGs can easily transfer the VSP into the actual surgery.

This paper is beneficial to study the development and applications of MRP-assisted CSGs in complex surgeries.

The purpose of this paper is to investigate the effect of nano-alumina sealant sealing treatment on corrosion behavior of the Fe-based amorphous coatings deposited on 304 stainless steel plates by atmospheric plasma spraying (APS) with different hydrogen flow rates.

The surface morphology and microstructure of the unsealed and sealed coatings were characterized by scanning electron microscopy and X-ray diffraction. The corrosion resistance of the coatings was investigated by potentiodynamic polarization test and electrochemical impedance spectroscopy experiment in 3.5 Wt.% NaCl solution.

Results show that a few microcracks and pores exist in the as-sprayed Fe-based amorphous coatings. The pores on the surface of the coatings after sealing treatment have been filled with nano-alumina sealant, which can effectively prevent corrosive medium from entering into coatings. Electrochemical tests results show that the corrosion resistance of the coatings before sealing treatment decreases with the increase of hydrogen flow rate and is significantly improved by sealing treatment.

The effect of nano-alumina sealant sealing treatment on corrosion resistance of APS-sprayed Fe-based amorphous coatings is revealed. The corrosion resistance of the as-sprayed Fe-based amorphous coating can be significantly improved by nano-alumina sealant sealing treatment because of the blocking effect of nano-alumina sealant on corrosive medium, which confirms that the application of nano-alumina sealant sealing treatment is of a practical option to improve corrosion resistance of as-sprayed thermal sprayed coatings.

The amorphous Al-Ni-Fe-Gd coatings were fabricated to improve anti-corrosion performance of offshore platforms.

The amorphous Al-Ni-Fe-Gd coatings were first fabricated on S355 steel using the laser thermal spraying.

The amorphous forming capability and corrosion resistance increases with the laser powers increasing.

The amorphous Al-Ni-Fe-Gd coatings were applied on S355 steel of offshore platforms to increase its long-term heavy and anti-corrosion protection.

The amorphous Al-Ni-Fe-Gd coatings were first fabricated using a laser thermal spraying, improving its anti-corrosion.

In this study, an amorphous Al-Ti-Ni coating was fabricated on S355 steel using an arc spraying, and its corrosion behavior immersed in 3.5 per cent NaCl solution for 720 h was discussed, which provided an experimental basis for the application of arc sprayed Al-Ti-Ni coating on S355 steel on marine platform.

An amorphous Al-Ti-Ni coating was sprayed on S355 structural steel using an arc spraying. The surface-interface morphologies, chemical element compositions and phases of the obtained Al-Ti-Ni coating were analyzed using a scanning electron microscope, energy dispersive spectrometer and X-ray diffractometer, respectively. The distributions of chemical elements on the coating surface and interface were analyzed using an energy spectrum scanning; the bonding mechanism between the coating and the substrate was also discussed.

Financial support for this research by the Key Research and Development Project of Jiangsu Province (BE2016052).

In this study, an amorphous Al-Ti-Ni coating was fabricated on S355 steel using an arc spraying, its corrosion behavior immersed in 3.5 per cent 25 NaCl solution for 720 h was discussed.