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Contract Manufacturers (CM, factory) can cultivate factory brand products by imitating Original Equipment Manufacturers' (OEM, brand owner) National Brand products, and compete with OEM through the online retailer, that is, factory encroachment. In practice, few consumers can identify the quality of those two products in the online market. Implementing blockchain technology (BTI) can help all consumers identify product quality but may change the operation decisions and incur implementation costs. This study aims to explore how will the BTI strategies affect participants' operation performance under the factory encroachment and delve into the decisions regarding NB product quality and CM encroachment.

This study constructs a three-level outsourcing supply chain comprising one contract manufacturer (CM, factory), one original equipment manufacturer (OEM) and one online retailer. By utilizing the Stackelberg game, the authors first compared the results between two strategic decisions of BTI and no-BTI by online retailers under the factory encroachment scenario. Then, the NB product quality decision and the CM's encroachment decision are also investigated.

BTI strategy can benefit all participants (triple win), which both occurs in exogenous and endogenous quality cases, and the triple win area will expand (shrink) as the BTI cost decreases (increases). In addition, the OEM will improve product quality to confront competition from the CM, and the OEM may not always benefit from the BTI, it depends on the maturity of the market. Interestingly, BTI could improve the consumer surplus when the proportion of novice consumers is low. Finally, this study also investigates the extended case that CM always encroaches into the market whether the online retailer choose BTI or not, which hurts OEM's profit and decreases the product quality.

This study sheds light on the strategic decisions of online retailers' BTI regarding supply chain members' profits, consumer surplus and social welfare under factory encroachment. It also demonstrates that the BTI strategy, under different quality decisions (endogenous and exogenous), can be more profitable for chain members and consumers.

When integrating smart elements offered by emergent technologies, libraries are facing the challenges of technological renovation and maintaining their operation using emerging technology. Given the importance of smart library, new technologies are needed in building new libraries or renovation of existing libraries. The purpose of this paper is to propose a risk warning system for library construction or renovation in the aspect of risk management.

The proposed Internet of Things (IoT)-based system consists of sensors that automatically monitor the status of materials, equipment and construction activities in real time. AI techniques including case-based reasoning and fuzzy sets are applied.

The proposed system can easily track material flow and visualize construction processes. The experiment shows that the proposed system can effectively detect, monitor and manage risks in construction projects including library construction.

Compared with existing risk warning systems, the proposed IoT-based system requires less data for making dynamic predictions. The proposed system can be applied to new builds and renovation of libraries.

Contact problems are among the most difficult ones in mechanics. Due to its practical importance, the problem has been receiving extensive research work over the years. The finite element method has been widely used to solve contact problems with various grades of complexity. Great progress has been made on both theoretical studies and engineering applications. This paper reviews some of the main developments in contact theories and finite element solution techniques for static contact problems. Classical and variational formulations of the problem are first given and then finite element solution techniques are reviewed. Available constraint methods, friction laws and contact searching algorithms are also briefly described. At the end of the paper, a bibliography is included, listing about seven hundred papers which are related to static contact problems and have been published in various journals and conference proceedings from 1976.

To provide valuable information for scholars to grasp the current situations, hotspots and future development trends of reliability analysis area.

In this paper, recent researches on efficient reliability analysis and applications in complex engineering structures like aeroengine rotor systems are reviewd.

The recent reliability analysis advances of engineering application in aeroengine rotor system are highlighted, it is worth pointing out that the surrogate model methods hold great efficiency and accuracy advantages in the complex reliability analysis of aeroengine rotor system, since its strong computing power can effectively reduce the analysis time consumption and accelerate the development procedures of aeroengine. Moreover, considering the multi-objective, multi-disciplinary, high-dimensionality and time-varying problems are the common problems in various complex engineering fields, the surrogate model methods and its developed methods also have broad application prospects in the future.

For the strong demand for efficient reliability design technique, this review paper may help to highlights the benefits of reliability analysis methods not only in academia but also in practical engineering application like aeroengine rotor system.

This paper aims to devote to the experimental analysis and modeling on the heat generation of angular contact ball bearings under vibration.

The experiments about vibration effect on bearing temperature are implemented. To explore the causes of bearing temperature rise, the shaft-bearing system is first simplified to a forced vibration model to analyze the bearing loads in vibration. Next, the vibratory-induced additional load is proposed and the spin power loss of balls is re-derived under vibration. The vibration-induced heat is integrated into a novel forecasting model of bearing power loss. For validation, the muti-node model for angular contact ball bearings is referred to create the thermal network of spindle front bearing, and then the contrast and discussion is done.

The simulation and test results both indicate that more energy is expended and more heat is generated with vibration. And the further quantitative comparisons between simulation results and experimental values of bearing temperature demonstrate the rationality and availability of constructed model on bearing heat generation.

The vibration-induced additional load is proposed and modeled, and the novel forecasting model for heat generation for high-speed angular contact ball bearings with vibration is constructed and validated.

This paper aims to deal with the problem of the global stabilization for a class of tension leg platform (TLP) nonlinear control systems.

It is well-known that, in general, the global asymptotic stability of the TLP subsystems does not imply the global asymptotic stability of the composite closed-loop system.

An effective approach is proposed to control chaos via the combination of fuzzy controllers, fuzzy observers and dithers.

If a fuzzy controller and a fuzzy observer cannot stabilize the chaotic system, a dither, as an auxiliary of the controller and the observer, is simultaneously introduced to asymptotically stabilize the chaotic system.

Thus, the behavior of the closed-loop dithered chaotic system can be rigorously predicted by establishing that of the closed-loop fuzzy relaxed system.

The aim of this paper is to review the literature on the prediction of cutting tool life. Tool life is typically estimated by predicting the time to reach the threshold flank wear width. The cutting tool is a crucial component in any machining process, and its failure affects the manufacturing process adversely. The prediction of cutting tool life by considering several factors that affect tool life is crucial to managing quality, cost, availability and waste in machining processes.

This study has undertaken the critical analysis and summarisation of various techniques used in the literature for predicting the life or remaining useful life (RUL) of the cutting tool through monitoring the tool wear, primarily flank wear. The experimental setups that comprise diversified machining processes, including turning, milling, drilling, boring and slotting, are covered in this review.

Cutting tool life is a stochastic variable. Tool failure depends on various factors, including the type and material of the cutting tool, work material, cutting conditions and machine tool. Thus, the life of the cutting tool for a particular experimental setup must be modelled by considering the cutting parameters.

This submission discusses tool life prediction comprehensively, from monitoring tool wear, primarily flank wear, to modelling tool life, and this type of comprehensive review on cutting tool life prediction has not been reported in the literature till now. The future suggestions provided in this review are expected to provide avenues to solve the unexplored challenges in this field.

(1) The shear lag effect and its additional deflection contribution to composite beams based on spatial grid elements were presented. (2) A refined spatial grid element analysis method that can simultaneously obtain the internal forces, displacements and stresses of various parts of a composite beam.

A refined spatial grid element analysis method.

The proposed method can directly obtain the internal forces and displacements of the joints of the composite beam roof, floor and web.

To comprehensively comprehend the mechanical behavior of double-girder steel plate composite girder bridge structures and facilitate refined analysis, this paper introduces a refined spatial grid element analysis model applicable to both the global and local domains.

Construction is a highly dynamic environment with numerous interacting factors that affect construction processes and decisions. Uncertainty is inherent in most aspects of construction engineering and management, and traditionally, it has been treated as a random phenomenon. However, there are many types of uncertainty that are not naturally modelled by probability theory, such as subjectivity, ambiguity and vagueness. Fuzzy logic provides an approach for handling such uncertainties. However, fuzzy logic alone has some limitations, including its inability to learn from data and its extensive reliance on expert knowledge. To address these limitations, fuzzy logic has been combined with other techniques to create fuzzy hybrid techniques, which have helped solve complex problems in construction. In this chapter, a background on fuzzy logic in the context of construction engineering and management applications is presented. The chapter provides an introduction to uncertainty in construction and illustrates how fuzzy logic can improve construction modelling and decision-making. The role of fuzzy logic in representing uncertainty is contrasted with that of probability theory. Introductory material is presented on key definitions, properties and methods of fuzzy logic, including the definition and representation of fuzzy sets and membership functions, basic operations on fuzzy sets, fuzzy relations and compositions, defuzzification methods, entropy for fuzzy sets, fuzzy numbers, methods for the specification of membership functions and fuzzy rule-based systems. Finally, a discussion on the need for fuzzy hybrid modelling in construction applications is presented, and future research directions are proposed.