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This paper aims at fabricating large metallic components with high deposition rates, low equipment costs through wire and wire and arc additive manufacturing (WAAM) method, in order to achieve the morphology and mechanical properties of manufacturing process, a bead morphology prediction model with high precision for ideal deposition of every pass was established.

The dynamic response of the process parameters on the bead width and bead height of cold metal transfer (CMT)-based AM was analyzed. A laser profile scanner was used to continuously capture the morphology variation. A prediction model of the deposition bead morphology was established using response surface optimization. Moreover, the validity of the model was examined using 15 groups of quadratic regression analyzes.

The relative errors of the predicted bead width and height were all less than 5% compared with the experimental measurements. The model was then preliminarily used with necessary modifications, such as further considering the interlayer process parameters, to guide the fabrication of complex three-dimensional components.

The morphology prediction of WAAMed bead is a critical issue. Most research has focused on the formability and defects in CMT-based WAAM and little research on the effect of process parameters on the morphology of the deposited layer in CMT-based WAAM has been conducted. To test the sensitivities of the processing parameters to bead size, the dynamic response of key parameters was investigated. A regression model was established to guide the process parameter optimization for subsequent multi-layer or component deposition.

This paper aimed to propose a novel fused-coating-based additive manufacturing (FCAM); the study of key process parameters and mechanical tests are performed to determine the proper parameters when building metal components.

Sn63Pb37 alloy is deposited in an induction heating furnace with a fused-coating nozzle to build metal parts on a copper-clad substrate. The process parameters including nozzle pressure, nozzle and substrate temperature and nozzle gap between substrate are analyzed and found to have great influence on parts quality. The mechanical property tests between the fused-coating and casting parts are performed in horizontal and vertical directions. Also, the optical microscopy images are used to ascertain under which conditions good bonding can be achieved.

A FCAM method is proposed, and the exploration study about the manufacturing process is carried out. The critical parameters are analyzed, and microscopy images prove the suitable temperature range that requires to fabricate metal parts. The mechanical tests confirm that tensile strength of printing parts is improved by 20.4 and 11.9 per cent in horizontal and vertical direction than casting parts. The experimental results indicate that there is a close relationship between process parameters and mechanical properties.

This paper proves that FCAM provides an alternative way to quickly make functional metal parts with good quality and flexibility compared with other additive manufacturing methods. Moreover, good mechanical property is achieved than conventional casting parts.

A study is made of the payoff matrix which is made up of grey interval number because of asymmetry information, player's finite knowledge and bounded rationality and all sorts of stochastic and non‐stochastic factors.

On the base of concept of equipollent, superior and inferior potential degree, the paper designs determinant rules of interval grey number potential relations, opens out player's decision‐making laws in the conditions of finite knowledge and logos. And it designs the grey game decision‐making rules which player choices maximum potential degree of grey game value (the most favorableness situation) under the cases of that there are all likely to be minimum potential degree of grey game value (the most disadvantage situation), which is a reliable way for both sides to accept.

The paper recognizes and defines overrated and underrated risk of potential optimal pure strategy in the grey game, designs arithmetic for determining player's overrated and underrated risk under the situation of potential optimal pure strategy.

The presents system meets the requirement of judging pure strategy solutions in the grey potential situation.

This paper builds up the system of judgment for grey potential.

With the continuous improvement of public–private partnership (PPP) projects, the participants' value creation goals are not only limited to achieving the basic performance objectives but also to realising value added. However, the effect of traditional contract management on realising the value creation objectives of PPP projects is limited. According to the view of multifunctional contract, joint-contract functions that integrate contract control and flexibility are likely to be effective in enhancing the value creation of PPP projects. This study aims to explore the effects of joint-contract functions on PPP project value creation and relevant influencing mechanism by investigating the mediating effect of in-role behaviour and extra-role behaviour.

After collecting 258 valid questionnaires from PPP professionals in China, this study used structural equation modelling to validate the hypotheses.

Contract control and flexibility can improve PPP project value creation. Specifically, contract control improves the achievement of the basic contract objectives of PPP projects, whereas contract flexibility enhances the achievement of the value-added of PPP projects. Moreover, only in-role behaviour mediates the effect of contract control on value creation. In addition, the mediating effect of extra-role behaviour on the impact of contract flexibility on value creation is stronger than that of in-role behaviour. The mediating effect of in- and extra-role behaviour is mainly reflected in the realisation of basic and value-added performance, respectively.

The findings of this study can help realise value creation in three ways. Firstly, new perspectives for PPP project value creation should be proposed by combining the improvement of contract objectives and the realisation of the participants' implicit demands. Secondly, the effects of different contract functions on value creation should be analysed instead of a single dimension of contractual governance. Thirdly, the mediating effects of different types of cooperation behaviour that may influence the relationship between contractual governance and value creation should be evaluated.

This study verifies the impacts of different contract functions on PPP project value creation. In addition, cooperative behaviour is embedded as a mediating variable, and the mediated transmission path from contract function to cooperative behaviour and further to PPP project value creation is systematically analysed.

This paper aims to analyse how both Lin’s birthplace identity and his Christian identity contributed to his fruitful public career and to ascertain which identity became the most significant.

Archival research is the main method used in this paper. The most important archives drawn from are the Daniel Tse Collection in the Special Collection and Archives of the Hong Kong Baptist University Library. Oral history has also been used in this paper to uncover more material that has not yet been discussed in existing scholarly works.

This paper argues that although Lin’s birthplace identity and social networks helped him to start his business career in Nam Pak Hong and develop into a leader in the local Chaozhou communities, these factors were insufficient to his becoming a respectable member of the Chinese elite in post-war Hong Kong. He became well known not because of his leading position in local Chaozhou communities or any great achievement he had obtained in business but because of his contribution to the development of Christian education. These achievements earned him a reputation as a “Christian educator”. Thus Lin’s Christian identity became more important than his birthplace identity in contributing to his successful public career.

This paper has value in showing how Christian influences interacted with various cultural factors in early Hong Kong. It also offers insights into Lin’s life and motivations as well as the history of the institutions he contributed to/founded. It not only furthers our understanding of the Chinese Christian business elite in early Hong Kong but also provides us with insights when further studying this group of people in other British colonies in Asia.