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This paper aims to anticipate the possible development direction of WAAM. For large-scale and complex components, the material loss and cycle time of wire arc additive manufacturing (WAAM) are lower than those of conventional manufacturing. However, the high-precision WAAM currently requires longer cycle times for correcting dimensional errors. Therefore, new technologies need to be developed to achieve high-precision and high-efficiency WAAM.

This paper analyses the innovations in high-precision WAAM in the past five years from a mechanistic point of view.

Controlling heat to improve precision is an effective method. Methods of heat control include reducing the amount of heat entering the deposited interlayer or transferring the accumulated heat out of the interlayer in time. Based on this, an effective and highly precise WAAM is achievable in combination with multi-scale sensors and a complete expert system.

Therefore, a development direction for intelligent WAAM is proposed. Using the optimised process parameters based on machine learning, adjusting the parameters according to the sensors’ in-process feedback, achieving heat control and high precision manufacturing.

In the process of Renminbi (RMB) internationalization, the heterogeneity and complexity in knowledge under the multicultural contexts have been considered as important factors that can have profound impacts on the cross-border flow of the RMB currency. Moreover, COVID-19, an exogenous shock, also triggers more in-depth reflection on the relationship between cross-border knowledge management and the financial risk governance. In addition, the needs to effectively respond to global risks and crises prompt the necessity in systematically establishing an effective cross-border knowledge management mechanism and innovatively solidifying the knowledge bases needed for the further internationalization of the RMB.

Based on the analysis on the current status of the RMB internationalization, this paper qualitatively explores some major challenges and difficulties encountered in the process of RMB internationalization from the perspectives of knowledge management and cross-cultural theories. To effectively mitigate these challenges and difficulties, discussions and recommendations centered on three main aspects: cross-cultural management; cognition; and innovation for the further development of the RMB internationalization are also presented in this paper.

Based on the analysis on the cross-border knowledge management and cross-cultural perspectives, this paper identifies three major challenges and difficulties that the RMB internationalization is encountering, including: cultural heterogeneity and its adverse impacts on the communication amongst economic entities; the existence of knowledge iceberg; and the difficulty it presents to cognition and financial innovation. Meanwhile, the authors also present recommendations on the development of the cross-border knowledge management mechanism for furthering the progress of internationalizing the RMB currency.

From the perspective of cross-border knowledge management, this study not only elaborates on the recommendations aimed at further promoting the RMB internationalization but also provides reference and guidance for the state, central banks and commercial banks to play better roles in furthering the RMB internationalization.

This paper creatively integrates the micro knowledge management into the macro process of RMB internationalization, thoroughly discusses two main challenges and difficulties encountered in the process of RMB internationalization from the unique perspective of cross-border knowledge management under the multicultural contexts and provides relevant recommendations for RMB’s further internationalization. This study also enriches the exploration of knowledge management outcome variables and further expands the research field of knowledge management.

Social media technology has changed donors' decision-making process in online philanthropy compared with traditional charity. How do IT affordances support donor perceptions and motivations in charitable crowdfunding? The purpose of this study is to explore how the five sub-dimensions of charitable crowdfunding IT affordances (i.e. visibility, association, meta-voicing, trading and security) afford initiators and platforms in motivating donors to support charitable crowdfunding projects.

This paper uses a quantitative research approach. An online survey was conducted to collect research data from WeChat users who had experienced charitable crowdfunding. A sample of 344 valid responses were received and analyzed.

The results show that four of the five IT affordances facilitate donors' perceptions (perceived emotions and trust) and motivations (intrinsic motivations and extrinsic motivations), and thereby increase behavioral intention on supporting charitable crowdfunding projects.

This study advances the affordances and online charity literature by examining the antecedents and outcome of perceptions and motivations that determining behavioral intention in more detail. The authors’ findings not only benefit researchers in explaining how technology helps donors perceiving projects and motivating them to donate online, but also assists practitioners in developing better charitable crowdfunding management strategy.

The purpose of this study is to investigate the contact models for contact and vibration features of cylindrical roller bearings (CRBs). CRBs are important parts of rotating machinery. The contact deformation between the roller and the raceway is an essential research topic for the CRBs. The contact deformation between the roller and the raceway can greatly affect vibration characteristics and fatigue life of the CRBs. In this investigation, six different methods are adopted to calculate the contact deformation, contact area width and contact stress between the roller and raceways of a CRB.

In this paper, the contact deformations and the contact stiffnesses between the roller and the raceway of a CRB obtained by various well-known empirical methods (Lundberg’s, Palmgren’s, Houpert’s, Cheng’s and Hertzian methods) are directly compared with those by the finite element (FE) method. A two degree-of-freedom (2 DOF) dynamic model of the CRB is applied to investigate the effects of the contact stiffness obtained by different line contact deformation calculation methods on the vibration characteristics, such as the root mean square (RMS), the peak to peak (PTP), the crest factor and the kurtosis of the displacement, velocity and acceleration of the inner raceway.

The computational results show that different calculation methods for the contact deformations between rollers and raceways have significant effects on the vibrations of the CRB. It is found that that the differences of computational results obtained by Palmgren’s and Lundberg’s models with respect to the FE method are smaller than those by the other three methods, i.e. Houpert’s, Cheng’s and Hertzain models. The amplitude and peak frequency of the frequency response functions from Palmgren’s method are much more similar to those from the finite element method. The above results indicate that Palmgren’s method is a better calculation method for predicting the contact deformations and dynamics of the CRBs.

This work adopts six different methods to calculate the contact deformation, contact area width and contact stress between the roller and raceways of a CRB. Moreover, a vibration model of a CRB is used to investigate the effect of contact stiffness obtained by the above methods on the vibrations of the CRB. The works can give some guidance for the accurate analytical method for calculating the contact deformations between rollers and raceways and the vibrations of the CRB.

The aim of this paper is to examine the effect of information disclosure by unlisted bond issuers on the stock price informativeness of listed firms in the same industry.

This paper takes advantage of information disclosure during the bond issuance and examines the spillover effect of unlisted bond issuers' information disclosure on listed firms in the stock market. The sample is composed of A-share firms listed on the Shanghai and Shenzhen stock exchanges from 2007 to 2018. All the data are obtained from the China Stock Market and Accounting Research and WIND databases. The impact of bond market information disclosure on price informativeness of listed firms in the same industry is identified through multivariate regression analyses.

Empirical results show that price informativeness of listed firms has a significantly positive association with the information disclosure of same-industry unlisted bond issuers. Further analyses show that the above finding is more significant when information disclosure of bond issuers is a more important channel for acquiring industry information (i.e. when industry is more concentrated, when economic uncertainty is high, and when industry information is less transparent) and understanding the industry competitive landscape (i.e. when bond issuers are relatively large, when bond issuers and listed firms have more direct product competition, when bond issuance firms are large-scale state-owned business groups), and when there are more cross-market information intermediaries (i.e. more cross-market institutional investors and more sell-side analysts). This paper indicates that information disclosure of bond issuers has a positive spillover effect on the stock market.

The novelty of the research is that the authors examine industry information spillover from unlisted firms to listed firms leveraging on unlisted firms' information disclosure in bond markets.

The purpose of this paper is to propose a multi-scale extended grey target decision method for dealing with multi-attribute decision-making problems with interval grey numbers whose value distribution information is asymmetrical.

First, the whitenization weight function (WWF) was adopted to show the value distribution information of interval grey numbers. The definitions of kernel, degree of greyness, relative kernel and whitenization standard deviation of interval grey numbers were given based on the WWF. Then, the relative kernel grey target and whitenization standard deviation grey target were constructed to take full advantage of the owned decision information. Finally, the relative bull’s-eye coefficient was proposed to rank the preference order of all alternatives.

The relative bull’s-eye coefficient reflects the influence of the decision information on decision results with respect to the mean level and value distribution of attribute values. Thus, the decision-maker could set the return and risk adjustment coefficient according to their preferences and select the optimal alternative with a high expected return and low risk.

The paper considers the valve distribution information of interval grey numbers, and a novel definition for kernels, degrees of greyness, relative kernels and whitenization standard deviations, which are given based on the WWF. The paper not only considers the influence of mean levels of decision information over decision results, but also takes the value distribution information into account.

The purpose of this paper is to propose a stable high-order absorbing boundary condition (ABC) based on new continued fraction for scalar wave propagation in 2D and 3D unbounded layers.

The ABC is obtained based on continued fraction (CF) expansion of the frequency-domain dynamic stiffness coefficient (DtN kernel) on the artificial boundary of a truncated infinite domain. The CF which has been used to the thin layer method in [69] will be applied to the DtN method to develop a time-domain high-order ABC for the transient scalar wave propagation in 2D. Furthermore, a new stable composite-CF is proposed in this study for 3D unbounded layers by nesting the above CF for 2D layer and another CF.

The ABS has been transformed from frequency to time domain by using the auxiliary variable technique. The high-order time-domain ABC can couple seamlessly with the finite element method. The instability of the ABC-FEM coupled system is discussed and cured.

This manuscript establishes a stable high-order time-domain ABC for the scalar wave equation in 2D and 3D unbounded layers, which is based on the new continued fraction. The high-order time-domain ABC can couple seamlessly with the finite element method. The instability of the coupled system is discussed and cured.

In order to find a way to create the artistic conception of modern landscape space, the spatial analysis of Daguanyuan is carried out from the perspective of literature in order to find out the method of creating the artistic conception of modern landscape space. Adopting the method of general to special, from theory to practice, the argument with special significance is analyzed from the most common phenomena, and this argument is applied to the method of practical cases. The results show that Daguanyuan space in literature needs the audience's ability to understand words, the perception of space in film and television needs the audience's strong memory and imaginative thinking, while the perception of Daguanyuan space in garden art needs only basic discrimination ability. After analyzing the effect of Daguanyuan space construction from the literary perspective, it is believed that the writing techniques of starting point - development - climax - ending, wanting to carry forward first and restraining first, and reserving foreshadows in literature can be used for reference in modern landscape design.

Varied accounts exist regarding the role of trust and satisfaction in online continuance intention and contexts within which this occurs. The purpose of this paper is to consider the moderating effect of structural assurance (SA) on satisfaction and trust and trust and continuance intention in a pure e-service context (online betting).

UK online bettors were surveyed with an instrument developed using validated variables and measurements, including continuance intention, satisfaction, trust (in vendor) and SA. Structural equation modeling with partial least squares was used to evaluate the measurement and structural model simultaneously.

SA positively moderates the trust–continuance intention relationship but not the satisfaction–trust relationship. SA is positively associated with trust.

The study contributes to research focused on exploring the moderating effects of trust and satisfaction on continuance intention where institution-based mechanisms are perceived to be effective and framed to assure success.

An over-reliance on context-specific mechanisms is inadequate; strategic approaches to trust must consider contextual and institutional mechanisms interdependently.

The paper addresses the need for research relating to the institutional context within which trust mechanisms operate. This research provides a novel contribution through an exploration of the moderating effects of SA on: trust and continuance intention; and satisfaction and trust (the authors also measure the direct effect of SA on trust). This paper is one of the first studies to examine these important concepts in this context. The online betting case allows for the exploration of risk where vendor-specific and contextual risk are both high.

A core challenge of assessing regional agricultural drought vulnerability (RADV) is to reveal what vulnerability factors, under which kinds of synergistic combinations and at what strengths, will lead to higher vulnerability: namely, the influence patterns of RADV.

A two-phased grey rough combined model is proposed to identify influence patterns of RADV from a new perspective of learning and mining historical cases. The grey entropy weight clustering with double base points is proposed to assess degrees of RADV. The simplest decision rules that reflect the complex synergistic relationships between RADV and its influencing factors are extracted using the rough set approach.

The results exemplified by China's Henan Province in the years 2008–2016 show higher degrees of RADV in the north and west regions of the province, in comparison with the south and east. In the patterns with higher RADV, the higher proportion of agricultural population appears in all decision rules as a core feature. A smaller quantity of water resources per unit of cultivated land area and a lower adaptive capacity, involving levels of irrigation technology and economic development, present a significant synergistic influence relationship that distinguishes the features of higher vulnerability from those of the lower.

The proposed grey rough combined model not only evaluates temporal dynamics and spatial differences of RADV but also extracts the decision rules between RADV and its influencing factors. The identified influence patterns inspire managerial implications for preventing and reducing agricultural drought through its historical evolution and formation mechanism.