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A dynamic model of the brake system considering the tangential and radial motion of the pad, and the torsion and wobbling motion of the disk is established in this paper. The influence of radial stiffness on the brake system is investigated under different tribological conditions. This paper aims to prove that sufficient radial stiffness is indispensable in the design of the brake system with good tribological performance.

By using the lumped mass method, a dynamic model of the brake system is established. A Stribeck-type friction model is applied to this model to correlate the frictional velocity, pressure and friction force. The stability of pad vibration is analysed by analysis methods. A new stability evaluation parameter is proposed to study the influence of radial stiffness on stability of pad vibration in a certain friction coefficient brake pressure range.

The findings show that the tangential vibration of the pad transits from periodic motion to quasi-periodic motion under a low tangential stiffness. The influence of radial stiffness on motion stability is stronger under a low nominal brake radius. The stability of the brake system can be ensured when the brake radius and radial stiffness are sufficient.

The influence of tangential stiffness of pad on stability of the brake system has been researched for decades. The insufficiency of stiffness in radial direction may also generate certain levels of instabilities but has not been fully investigated by modelling approach. This paper reveals that this parameter is also strongly correlated to nonlinear vibration of the brake pad.

The purpose of this paper is to study stability analysis, solition solutions and Gaussian solitons of the generalized nonlinear Schrödinger equation with higher order terms, which can be used to describe the propagation properties of optical soliton solutions.

The authors apply the ansatz method and the Hamiltonian system technique to find its bright, dark and Gaussian wave solitons and analyze its modulation instability analysis and stability analysis solution.

The results imply that the generalized nonlinear Schrödinger equation has bright, dark and Gaussian wave solitons. Meanwhile, the authors provide the graphical analysis of such solutions to better understand their dynamical behavior. Some constraint conditions are provided which can guarantee the existence of solitons. The authors analyze its modulation instability analysis and stability analysis solution.

These results may help us to further study the local structure and the interaction of solutions in generalized nonlinear Schrödinger -type equations. The authors hope that the results provided in this work can help enrich the dynamic behavior of the generalized nonlinear Schrödinger--type equations.

The purpose of this study is to examine the lump solutions of the (3 + 1)-dimensional nonlinear evolution equations by considering a (3 + 1)-dimensional generalized Kadomtsev–Petviashvili (gKP) equation and a (3 + 1)-dimensional variable-coefficient generalized B-type Kadomtsev–Petviashvili (vcgBKP) equation as examples.

Based on Hirota’s bilinear theory, a direct method is used to examine the lump solutions of these two equations.

The complete non-elastic interaction solutions between a lump and a stripe are also discussed for the equations, which show that the lump solitons are swallowed by the stripe solitons.

The dynamics of these solutions are analyzed to enrich the diversity of the dynamics of high-dimensional KP-type nonlinear wave equations.

The purpose of this paper is to propose a approach for data visualization and industrial process monitoring.

A deep enhanced t-distributed stochastic neighbor embedding (DESNE) neural network is proposed for data visualization and process monitoring. The DESNE is composed of two deep neural networks: stacked variant auto-encoder (SVAE) and a deep label-guided t-stochastic neighbor embedding (DLSNE) neural network. In the DESNE network, SVAE extracts informative features of the raw data set, and then DLSNE projects the extracted features to a two dimensional graph.

The proposed DESNE is verified on the Tennessee Eastman process and a real data set of blade icing of wind turbines. The results indicate that DESNE outperforms some visualization methods in process monitoring.

This paper has significant originality. A stacked variant auto-encoder is proposed for feature extraction. The stacked variant auto-encoder can improve the separation among classes. A deep label-guided t-SNE is proposed for visualization. A novel visualization-based process monitoring method is proposed.

This paper aims to present a robust design approach to realize disturbance attenuation for a yaw – pitch gimballed system subject to actuator saturation and disturbances.

To minimize the impacts of disturbances in the presence of saturation nonlinearity and acquire desired response performance, the control approach is of double closed-loop configuration. State feedback controllers are synthesized via convex optimization and used to stabilize the inner loops; robust controllers are synthesized via mixed H _∞ optimization and used to stabilize the outer loops.

It is shown through performance simulations that the proposed control scheme is effective in terms of command following, stability and disturbance attenuation.

The presented robust control approach provides a theoretical method to facilitate designing a stable servo control loop for a yaw – pitch gimballed seeker.

This paper supplies an effective way of addressing stabilization problem induced from actuator saturation and system uncertainties.

The purpose of this research is to investigate how to introduce a financing scheme to tackle the manufacturer's capital constraint problem, discuss the effects of data-driven marketing (DDM) quality, cross-channel-return (CCR) rate and financing interest rate on the members' pricing and delivery-lead-time decisions and optimal performances, and analyzes `how to achieve the coordination within a dual-channel supply chain (DSC) by contract coordination.

This work establishes a DSC model with DDM, and the offline retailer can provide internal financing to the capital-constrained online manufacturer. The demand under the price is determined based on DDM quality, customer channel preference and delivery lead time. Then, combined with the Stackelberg game, the optimal pricing and delivery-lead-time decisions are discussed under the inconsistent and consistent pricing strategies with decentralized and centralized systems. Furthermore, it designs a manufacturer-revenue sharing contract to coordinate the members under the two pricing strategies.

(1) The increase of DDM quality will reduce the delivery-lead-time under the inconsistent or consistent pricing strategy and will push the selling prices; (2) The growth of the CCR rate will raise selling prices and extend the delivery-lead-time under the decentralized decision; (3) Under price competition, the offline selling price is higher than the online selling price when customers prefer the offline channel and vice versa; (4) The retailer and the manufacturer can achieve a win-win situation through a manufacturer-revenue sharing contract.

This paper contributes to the studies related to DSC by investigating pricing and delivery-lead-time decisions based on DDM, CCR, internal financing and supply chain contract and proposes some managerial implications.

The revolution brought about by the internet and the World Wide Web has led to the development of numerous e-Tendering systems for public sector tendering that have automated various aspects of the manual tendering processes that are known to experience numerous problems. However, one key area that has not been fully addressed is the automation of the evaluation of public tenders based on group decision-making. This paper presents part of the development of a Web-based e-tendering system called Nigerian Public Sector eTender (NPS-eTender) that automate the evaluation of public sector tenders based on group decision-making.

The system was developed using object-oriented methodologies. Specifically, Ripple and unified process methodologies were adopted.

The results of the system validation showed that NPS-eTender has an average rating of 74% with respect to correct and accurate modelling of the existing tendering domain and an average rating of 67.6% with respect to its potential to enhance the proficiency of public sector tendering in Nigeria. Based on the results of the validation, it can be concluded that the automation of the tender evaluation process can lead to a more proficient tendering process.

This research has contributed to the development of an e-Tendering system for the public sector that supports the whole tendering lifecycle including the automation of evaluation of public tenders based on group decision-making.

This study aims to review the recent advancements in high entropy alloys (HEAs) called high entropy materials, including high entropy superalloys which are current potential alternatives to nickel superalloys for gas turbine applications. Understandings of the laser surface modification techniques of the HEA are discussed whilst future recommendations and remedies to manufacturing challenges via laser are outlined.

Materials used for high-pressure gas turbine engine applications must be able to withstand severe environmentally induced degradation, mechanical, thermal loads and general extreme conditions caused by hot corrosive gases, high-temperature oxidation and stress. Over the years, Nickel-based superalloys with elevated temperature rupture and creep resistance, excellent lifetime expectancy and solution strengthening L12 and γ´ precipitate used for turbine engine applications. However, the superalloy’s density, low creep strength, poor thermal conductivity, difficulty in machining and low fatigue resistance demands the innovation of new advanced materials.

HEAs is one of the most frequently investigated advanced materials, attributed to their configurational complexity and properties reported to exceed conventional materials. Thus, owing to their characteristic feature of the high entropy effect, several other materials have emerged to become potential solutions for several functional and structural applications in the aerospace industry. In a previous study, research contributions show that defects are associated with conventional manufacturing processes of HEAs; therefore, this study investigates new advances in the laser-based manufacturing and surface modification techniques of HEA.

The AlxCoCrCuFeNi HEA system, particularly the Al0.5CoCrCuFeNi HEA has been extensively studied, attributed to its mechanical and physical properties exceeding that of pure metals for aerospace turbine engine applications and the advances in the fabrication and surface modification processes of the alloy was outlined to show the latest developments focusing only on laser-based manufacturing processing due to its many advantages.

It is evident that high entropy materials are a potential innovative alternative to conventional superalloys for turbine engine applications via laser additive manufacturing.

The purpose of this paper is to find homoclinic breather waves, rogue waves and soliton waves for a (3 + 1)-dimensional generalized Kadomtsev–Petviashvili (gKP) equation, which can be used to describe the propagation of weakly nonlinear dispersive long waves on the surface of a fluid.

The authors apply the extended Bell polynomial approach, Hirota’s bilinear method and the homoclinic test technique to find the rogue waves, homoclinic breather waves and soliton waves of the (3 + 1)-dimensional gKP equation.

The results imply that the gKP equation admits rogue waves, homoclinic breather waves and soliton waves. Moreover, the authors also find that rogue waves can come from the extreme behavior of the breather solitary wave. The authors analyze the propagation and interaction properties of these solutions to better understand the dynamic behavior of these solutions.

These results may help us to further study the local structure and the interaction of waves in KP-type equations. It is hoped that the results can help enrich the dynamic behavior of such equations.

The purpose of this paper is to study the realization of turn‐over‐wok movement for a cooking robot.

First, the authors introduce the cooking robot's movement mechanism and its realization methods and then analyze the movement geometric of the movement mechanism. The authors conduct the force analysis of the material in the wok motion and suppose the moving situation of mass point m when turning over the wok and shaking the wok.

The problem of the cooking robot simulating the special cooking motion made by a chef is solved.

The robot is applicable to being a cooking robot for Chinese dishes.

The paper shows how to optimize the effect of material moving track and satisfies the requirements of wok motion of cooking robot.