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There is coupling between the branches of mobile parallel robots, similar to traditional parallel mechanisms, but there is currently relatively little research on the coupling problem between the branches of mobile parallel robots.

This study optimizes the coupling analysis method of traditional parallel mechanisms, treats the mobile parallel mechanism as a whole, takes the motion of the active pair as input and the overall motion of the mobile parallel mechanism as output and analyzes the input–output characteristics of the mobile parallel mechanism. Moreover, this study applies this theory to a mobile parallel mechanism, designs control logic and finally conducts simulation and physical verification.

This study proposes a coupling analysis method suitable for parallel mobile robots and designs the control logic of their active pair based on the results of their coupling analysis. This study designs a multimode variable coupling parallel mobile robot, which can change the coupling of the mechanism by changing its own branch chain structure, so that it can switch between different coupling configurations to meet the different needs brought by different terrains.

The work presented in this paper propose a method for analyzing the coupling of mobile parallel robots and simplify their control logic by applying coupling theory to the design of mobile parallel robots. This study conducts simulation and physical experiments, thereby filling the gap in the coupling analysis of parallel mobile robots and laying the foundation for the research of uncoupled parallel mobile robots.

This chapter empirically examines the relationship between defense expending, budget deficits, and income redistribution in India for the period 1970–2009. The analysis is based on an autoregressive distributed lag model (ARDL) popularized by Pesaran and Shin (1999). Empirical estimates reveal that military spending in India is indeed associated with income redistribution. The empirical approach indicates that there exists a long-run relationship between transfer payments as a percentage in GDP (TP), defense expenditures as a percentage in GDP (ME), and budget deficits as a percentage in GDP (DEF) in India. Defense expenditures as a percentage in GDP and the budget deficits as a percentage in GDP have positive and significant impacts on transfer payments in the same fiscal year. But the budget deficit as a percentage in GDP has a negative and significant impact on transfer payments as a percentage in GDP in the next fiscal year.

The purpose of this paper is to examine the direct effects of Internet use on rural residents' income growth and the indirect effects of increasing their income by promoting rural residents' entrepreneurial and non-agricultural employment.

Regarding the implementation of the rural revitalization strategy, based on the 2016CFPS data, multiple linear regression analysis and mediation effect analysis are used. To decrease the potential endogeneity of the model, we used the instrumental variable in the model.

The results show that: (1) Internet use has a direct effect on rural residents' income growth; (2) rural residents' entrepreneurial or non-agricultural employment affects the mechanism of Internet use and their income growth, so that can perform an indirect promotion effect; (3) the direct promotion effect of Internet use is stronger than the indirect promotion effect of entrepreneurship and non-agricultural employment.

The effect of using Internet for the income growth of Chinese farmers has been confirmed by some scholars, but the specific mechanism is still relatively vague. The originality is to consider the intermediary transmission effect of entrepreneurship and non-agricultural employment in the study of the impact of Internet use on Chinese farmers' income growth, and use the mediation effect model for empirical analysis. The empirical research results further reveal this mechanism.

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.

Health-related online fake news (HOFN) has become a major social problem. HOFN can lead to the spread of ineffective and even harmful remedies. The study aims to understand Internet users' responses to HOFN during the coronavirus (COVID-19) pandemic using the protective action decision model (PADM).

The authors collected pandemic severity data (regional number of confirmed cases) from government websites of the USA and China (Studies 1 and 2), search behavior from Google and Baidu search engines (Studies 1 and 2) and data regarding trust in two online fake news stories from two national surveys (Studies 2 and 3). All data were analyzed using a multi-level linear model.

The research detected negative time-lagged relationships between pandemic severity and regional HOFN search behavior by three actual fake news stories from the USA and China (Study 1). Importantly, trust in HOFN served as a mediator in the time-lagged relationship between pandemic severity and search behavior (Study 2). Additionally, the relationship between pandemic severity and trust in HOFN varied according to individuals' perceived control (Study 3).

The authors' results underscore the important role of PADM in understanding Internet users' trust in and search for HOFN. When people trust HOFN, they may seek more information to implement further protective actions. Importantly, it appears that trust in HOFN varies with environmental cues (regional pandemic severity) and with individuals' perceived control, providing insight into developing coping strategies during a pandemic.

This paper seeks to discuss the genealogical sources for Chinese immigrants as well as the settlement of Chinese in the USA and the historical evolution of Chinese names, their origins, arrangement and development. It aims to cover the origins of various classes of Chinese surnames, followed by the content description of a traditional genealogical book for jiapu.

The paper researches the various ways that a Chinese person can find out about their ancestry.

The paper reveals the roles of libraries, including serving the needs of patrons interested in genealogical research, preserving and interpreting information through oral and family history projects and collaborating with other libraries through interlibrary loan, document delivery, library consortia, collection management and international resource‐sharing.

The study provides information on where and how to locate the genealogical resources for researching the genealogy of a Chinese family.

The paper analyzes the value of genealogical research as a documentary source for population history, life expectancy in a clan, marriages and family connections, as well as lineage organizations and inter‐lineage relations.

This paper aims to prepare high corrosion-resistant chromium-free zinc-aluminum (Zn–Al) coatings reinforced with multi-walled carbon nanotubes (MWCNTs) and nano-ZnO particle composites.

The morphology, composition and corrosion resistance of the coatings were analyzed by electrochemical tests, water contact angle tests, immersion tests, scanning electron microscopy/energy dispersive spectrometer and X-ray diffraction.

The composite coating with 0.3% MWCNTs and 0.5% nano-ZnO particles demonstrated both high shielding performance and cathodic protection performance, which was attributed to the porosity filling of MWCNTs and nano-ZnO particles together with the electrical connection of MWCNTs between the zinc and aluminum powders.

This work laid an experimental foundation for the preparation and corrosion mechanism of high corrosion-resistant chromium-free Zn–Al coating reinforced with MWCNTs and nano-ZnO particles.

The purpose of this study is to optimize and improve conventional welding using EMF assisted technology. Current industrial production has put forward higher requirements for welding technology, so the optimization and improvement of traditional welding methods become urgent needs.

External magnetic field assisted welding is an emerging technology in recent years, acting in a non-contact manner on the welding. The action of electromagnetic forces on the arc plasma leads to significant changes in the arc behavior, which affects the droplet transfer and molten pool formation and ultimately improve the weld seam formation and joint quality.

In this paper, different types of external magnetic fields are analyzed and summarized, which mainly include external transverse magnetic field, external longitudinal magnetic field and external cusp magnetic field. The research progress of welding behavior under the effect of external magnetic field is described, including the effect of external magnetic field on arc morphology, droplet transfer and weld seam formation law.

However, due to the extremely complex physical processes under the action of the external magnetic field, the mechanism of physical fields such as heat, force and electromagnetism in the welding has not been thoroughly analyzed, in-depth theoretical and numerical studies become urgent.

Prior studies fail to reach a consensus on the effects of extrinsic motivation (EM) on knowledge contribution in virtual communities. To fill this research gap, this research proposes two mechanisms of EM – direct effect versus indirect effect via intrinsic motivation (IM) – and introduces prosocial motivation (PSM) as the moderator to define the valence of these two mechanisms.

This research adopts structural equation modeling to validate hypotheses based on 448 responses from XiaoMi online community users.

The results of the moderated mediation analysis show that the direct effect, indirect effect via IM and total effect of EM on knowledge contribution are contingent on the level of PSM. Specifically, as the level of PSM increases, the direct, indirect and total effects of EM on knowledge contribution and the effects of EM on IM change from positive to insignificant and then to negative. Although IM constantly plays an important role across levels of PSM, its effect is stronger when the degree of PSM is high.

This paper advances knowledge of an integrated framework of EM by simultaneously describing its direct and indirect effects, describing its positive and negative effects and untangling the boundary conditions under which each effect of EM applies.