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The coal-based synthetic natural gas slag (CSNGS) is a solid waste remaining from the incomplete combustion of raw coal to produce gas. With the continuous promotion of efficient and clean utilization of coal in recent years, the stockpiling of CSNGS would increase gradually, and it would have significant social and environmental benefits with reasonable utilization of CSNGS. This study prepared a new geopolymer by mixing CSNGS with PC42.5 cement in a certain mass ratio as the precursor, with sodium hydroxide and sodium silicate solution as the alkali activators.

The formulation of coal-based synthetic natural gas slag geopolymer (CSNGSG) was determined by an orthogonal test, and then the strength mechanism and microstructure of CSNGSG were characterized by multi-scale tests.

The results show that the optimum ratio of CSNGSG was a sodium silicate modulus of 1.3, an alkali dosage of 21% and a water cement ratio of 0.36 and the maximum unconfined compressive strength of CSNGSG at 7 d was 26.88 MPa. The increase of curing temperature could significantly improve the compressive strength of CSNGSG, and the curing humidity had little effect on the compressive strength of CSNGSG. The development of the internal strength of CSNSG at high temperatures consumed SiO₂, Al₂O₃ and CaO and the intensity of corresponding crystalline peaks decreased.

Moreover, the vibration of chemical bonds in different wavenumbers also revealed the reaction mechanism of CSNSG from another perspective. Finally, the relevant test results indicated that CSNGS had practical application value as a raw material for the preparation of geopolymer cementing materials.

Merchant guild culture derives from business practices associated with medieval and early modern merchant guilds. This study aims to investigate the nexus between merchant guild culture and firm internationalization as well as the factors that moderate this nexus.

Based on the distribution of the ten merchant guilds in China and data on Chinese listed companies, this study uses the geographical proximity-based method to measure the intensity of merchant guild culture, which is the nearest distance between the ten merchant guilds’ origins and each firm’s registered address.

This study provides robust evidence that merchant guild culture positively relates to the degree of firm internationalization. It also documents that this nexus is stronger for firms with overseas background executives and those situated in highly marketized regions.

The findings of this study have valuable implications for both governments and firms. Governments can leverage local cultures to promote the internationalization of domestic firms, particularly in emerging economies with rich cultural heritage. Firms can further enhance their internationalization efforts by hiring more executives with overseas backgrounds.

This study advances the imprinting literature, provides a novel perspective on the antecedents of firm internationalization and expands research on the contemporary value of historical business culture.

The purpose of this paper is to research comprehensively into the development pattern of the world's 110‐meter hurdles of the coming two years. It aims to provide a detailed reference to the preparation of the 2012 London Olympics.

The paper uses the GM (2, 1) model, GM (1, 1) model, GM (1, 1) residual fixing model, and the method of recursive compensation by grey numbers of identical dimensions.

In 2012, the strongest athletes of 110‐meter hurdles are predicted to be: USA athlete Oliver, USA athlete Ash and Cuba athlete Robles. Liu Xiang has the possibility of winning the medal in the 2012 London Olympics.

Because every athlete is an individual that grows up gradually, there are two characteristics in his information: continuity and incompleteness. We can use the grey system methods.

The paper successfully applies the grey prediction to the case study in the field of competitive sports.

The assembly simulation in tolerance analysis is one of the most important steps for the tolerance design of mechanical products. However, most assembly simulation methods are based on the rigid body assumption, and those assembly simulation methods considering deformation have a poor efficiency. This paper aims to propose a novel efficient and precise tolerance analysis method based on stable contact to improve the efficiency and reliability of assembly deformation simulation.

The proposed method comprehensively considers the initial rigid assembly state, the assembly deformation and the stability examination of assembly simulation to improve the reliability of tolerance analysis results. The assembly deformation of mating surfaces was first calculated based on the boundary element method with optimal initial assembly state, then the stability of assembly simulation results was assessed by the density-based spatial clustering of applications with noise algorithm to improve the reliability of tolerance analysis. Finally, combining the small displacement torsor theory, the tolerance scheme was statistically analyzed based on sufficient samples.

A case study of a guide rail model demonstrated the efficiency and effectiveness of the proposed method.

The present study only considered the form error when generating the skin model shape, and the waviness and the roughness of the matching surface were not considered.

To the best of the authors’ knowledge, the proposed method is original in the assembly simulation considering stable contact, which can effectively ensure the reliability of the assembly simulation while taking into account the computational efficiency.

This paper aims to improve the tribocorrosion properties of 316L, thus WC/Ni60 coated 316L was prepared by thermal spraying technique.

Composition and microstructure of WC/Ni60 coating was investigated, and tribological properties of 316 L and WC/Ni60 coating were studied under dry sliding, deionized water and artificial seawater.

The results showed that WC/Ni60 coating was lamellar structure, and the phase composition consisted of γ-Ni solid solution, carbides and borides. Furthermore, the hardness and corrosion resistance of 316 L in static seawater and wear resistance in dry sliding were improved by WC reinforced nickel-based coating. Furthermore, tribocorrosion results demonstrated that wear resistance of WC/Ni60 coating was also significantly better than 316 L, especially for higher load at artificial seawater. The reason can be attributed to the fact that the passive film of WC/Ni60 coating consisted of tungsten carbide, Ni(OH)2 and FeOOH for WC/Ni60 coating and only FeOOH for 316 L.

According to this study, it can be concluded that WC phases acted as a role in resisting the wear damages. Meanwhile, Ni-based materials performed well in corrosion resistance. Thus, the combined-effect Ni-based alloys and WC phases in WC/Ni60 coating showed better tribocorrosion performance than 316 L.

The step effect and support structure generated by the manufacturing process of fused deposition molding parts increase the consumables cost and decrease the printing quality. Multiorientation printing helps improve the surface quality of parts and reduce support, but path interference exists between the printing layer and the layers printed. The purpose of this study is to design printing paths between different submodels to avoid interference when build orientation changed.

Considering support constraint, build orientation sequence is designed for submodels decomposed by model topology. The minimum printing angle between printing layers is analyzed. Initial path through the oriented bounding box is planned and slice interference relationship is then detected according to the projection topology mapping. Based on the relationship matrix of multiorientation slice, feasible path is calculated by directed graph (DG). Final printing path is determined under support constraint and checked by minimum printing angle. The simulation model of the robotic arm is established to verify the accessibility of printing path under the constraint of support and slice.

The proposed method can reduce support structure, decrease volume error and effectively solve the interference problem of the printing path for multiorientation slice.

The method based on projection topology mapping greatly improves the efficiency of interference detection. A feasible path calculated through DGs ensures the effectiveness of the printing path with the constraint of support and slice.

Accurately identifying the risk of poverty-returning is a complex and critical challenge in current poverty alleviation efforts. However, there is currently no study on evaluation methods for the risk of poverty-returning. This study aims to establish a robust and systematic approach for an evaluation framework for the risk of poverty-returning.

Based on relevant assessment criteria, a maximum deviation method was established to identify the weights of the indicators. A complex evaluation methodology using prospect theory (PT), a q-rung orthopair fuzzy set (QrOFS) and evaluation relying on distance from average solution [EDAS] (QrOFS-PT-EDAS) was developed to evaluate the poverty-returning risks. Some policy recommendations to reduce the risk of poverty-returning have also been put forward.

His study identifies the risk factors of poverty relapse from nine aspects, including natural disasters, accidents and policy-driven poverty relapse. In addressing the evaluation challenge arising from uncertain decision-making, the QrOFS aligns more with people’s thinking habits and expression methods in complex environments. The proposed hybrid evaluation framework accurately measures the poverty-returning risk, which is beneficial for the formulation of policy recommendations.

A scientific and comprehensive assessment system index for poverty-returning is constructed. A hybrid QrOFS-PT-EDAS framework is presented to make the evaluation results more scientific and objective. Several strategic recommendations for reducing the poverty-returning risk are presented. This study offers a novel framework for assessing poverty-returning issues that can be extended to many other areas.

The purpose of this paper is to focus on how corporate social responsibility (CSR) (i.e. responsibility to customers, employees and society) influences customer behavioural loyalty in the hotel industry. The mediating effects of brand image and customer trust on the relationship between CSR and customer behavioural loyalty are also considered.

In total, 298 valid responses to questionnaire surveys were collected from a convenience sample in China in 2017. A structural equation model was used to test the hypotheses.

Hotel customer behavioural loyalty can be enhanced by CSR performance. Performance in each of the three CSR domains positively impacted customer behavioural loyalty to different degrees. The impact of CSR on the customer had the strongest influence on Chinese customers’ behavioural loyalty among the three CSR domains of customer, employee and society. Brand image and customer trust were found to be mediators of the relationship between CSR performance and customer behavioural loyalty.

The current research contributes to the literature by demonstrating that CSR activities are not all equally effective. Results reveal that the society dimension of CSR had the strongest impact on Chinese customers’ brand image of hotels among the three CSR dimensions investigated. In terms of Chinese hotel customers’ trust, the CSR–customer dimension plays the most effective role. The findings also support the notion that Chinese consumers are beginning to use CSR information to evaluate hotels.

A large number of residential buildings in hot summer and cold winter zone of China are non-energy efficient with poor indoor thermal conditions. Retrofitting residential buildings with energy efficiency measures is thus important for residents. However, this work progressed slowly because practically applicable measures that not only have high energy savings but also improve indoor thermal performance have not been studied. Thus, this paper carried out a simulation study on the selection of suitable energy saving measures for residential buildings in hot summer and cold winter zone of China. Five potential energy saving options are considered and the energy, indoor thermal comfort and economic performance are compared. The results show that adding movable solar shades is the optimum option with all performance indices ranking first. Meanwhile, this measure is also the only acceptable energy saving solution for residents since its payback period is less than the lifespan of a building. As a conclusion, it is recommended to use movable solar shades as a first priority when retrofitting residential buildings.