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The buried pipe element method can be used to calculate the temperature of mass concrete through highly efficient computing. However, in this method, temperatures along cooling pipes and the convection coefficient of the cooling pipe boundary should be improved to achieve higher accuracy. Thus, there is a need to propose a method for improvement.

According to the principle of heat balance and the temperature gradient characteristics of concrete around cooling pipes, a method to calculate the water temperature along cooling pipes using the buried pipe element method is proposed in this study. By comparing the results of a discrete algorithm and the buried pipe element method, it was discovered that the convection coefficient of the cooling pipe boundary for the buried pipe element method is only related to the thermal conductivity of concrete; therefore, it can be calculated by inverse analysis.

The results show that the buried pipe element method can achieve the same accuracy as the discrete method and simulate the temperature field of mass concrete with cooling pipes efficiently and accurately.

This new method can improve the calculation accuracy of the embedded element method and make the calculation results more reasonable and reliable.

Although governments have used social media platforms to interact with the public in an attempt to minimize anxiety and provide a forum for public discussion during the pandemic, governments require sufficient crisis communication skills to engage citizens in taking appropriate action effectively. This study aims to examine how the National Health Commission of China (NHCC) has used TikTok, the leading short video–based platform, to facilitate public engagement during COVID-19.

Building upon dual process theories, this study integrates the activation of information exposure, prosocial interaction theory and social sharing of emotion theory to explore how public engagement is related to message sensation value (MSV), media character, content theme and emotional valence. A total of 354 TikTok videos posted by NHCC were collected during the pandemic to explore the determinants of public engagement in crises.

The findings demonstrate that MSV negatively predicts public engagement with government TikTok, but that instructional information increases engagement. The presence of celebrities and health-care professionals negatively affects public engagement with government TikTok accounts. In addition, emotional valence serves a moderating role between MSV, media characters and public engagement.

Government agencies must be fully aware of the different combinations of MSV and emotion use in the video title when releasing crisis-related videos. Government agencies can also leverage media characters – health professionals in particular – to enhance public engagement. Government agencies are encouraged to solicit public demand for the specific content of instructing information through data mining techniques.

The purpose of this paper is to analyse the development and evolution of industrial innovation ecosystems of Around-Tongji Knowledge Economy Circle from the three levels mentioned above, focusing on knowledge-producing populations, core populations and service-supporting populations, and to further develop this research framework by combining with the latest developments.

Based on the five-helix theory and economic census statistical data, this paper adopts geographic information system technology and examines the characteristics of the industrial innovation ecosystem and the synergistic evolution process in Around-Tongji knowledge economy circle.

The knowledge product populations lead the development of industries in Around-Tongji Knowledge Economy Circle. It contributes political capital output for the government. It innovates community cooperation and governance mode, and it improves the natural ecological environment. In the face of the changes and challenges in the development environment, the future development must be recognised from the height of the iterative development of the interaction mode between university knowledge production and economic and social development.

Based on the five-helix theory and economic census statistical data, this paper examines the characteristics of the industrial innovation ecosystem and the synergistic evolution process in Around-Tongji Knowledge Economy Circle. It further expands the research framework used to develop a synergistic evolution model, which reveals the interactive and synergistic relationship among the populations and the evolution characteristics of the entire industrial innovation ecosystem. This paper also provides useful perspectives for the study of the industrial innovation ecosystem.

This paper aims to study the synergistic effect of graphene sponge on the thermal properties and shape stability of composite phase change material (PCM).

Graphene oxide sponge is first prepared from an aqueous solution of graphene oxide by freeze-drying method. The oxidized graphene sponge is reduced by hydrazine hydrate. Finally, use vacuum impregnation method to introduce paraffin into graphene sponge to prepare composite PCM.

Graphene sponge is used to improve the shape stability of paraffin wax and improves the thermal conductivity and latent heat of the composite PCM. The thermal conductivity increases by 200 per cent and the composite PCM has excellent reliability in 100 melt-freezing cycles.

A simple way for fabricating composite PCM with high thermal conductivity and latent heat which has the potential to be used as thermal storage materials without container encapsulation has been developed by using graphene sponge and paraffin.

The materials and preparation methods with special structure and properties in this paper provide a new idea for the research of PCM, which can be widely used in the fields of energy conversion and storage.

This paper aims to systematically expound the theory and development background of supply chain finance and blockchain, design a railway freight supply chain financial platform based on blockchain, determine the risk management system and business support system of supply chain finance business and analyze the value generated by the combination of supply chain finance business and blockchain.

Investigation and research method; Prototype method; Model method; Value analysis.

The business model integrating supply chain finance and blockchain technology will bring great changes to freight industry. The development of supply chain finance is beneficial to the healthy development of the core participants of railway freight transport business and its upstream and downstream ecosystems. It links commerce, logistics, warehousing and financial services together and builds an industry-integrated ecological service platform through information technology platform and supporting system, taking data as the basis and combining information technology such as blockchain as innovative means.

This paper will provide important reference value for related research. This paper innovatively designs the supply chain financial platform of freight transportation industry-integrating blockchain technology and analyzes its business model, technical system, risk management and control system and value system in detail, which will provide technical support for the innovative reform of freight information technology and realize the stable and high-speed development of freight logistics informationization.

Although internet plus government platforms (IPGPs) are being increasingly used by citizens around the world, questions emerge regarding the public adoption, utilization and use of IPGPs. This study aims to explore the determinants of citizens’ differentiated IPGPs usage behaviors.

An analytical framework has been built upon the rational choice theory and the cultural dimension theory. The present study draws on a survey of 866 citizens from Guangzhou, Wuhan and Chengdu.

The empirical findings suggest that the perceived functional benefits and personalization features both significantly affect citizens’ informational, service and participatory uses of IPGPs, to varying degrees. Furthermore, long-term orientation plays a moderating role in the relationship between perceived functional benefits and the service use of IPGPs.

The findings demonstrate that the public’s rational choice of a new digitalized service channel depends on to what extent and to what degree the absolute and relative benefits they consider important compare to other possible channels. Users also consider how the new service channel satisfies their personalized demands of digitalized services. Also, users’ long-term orientation can affect their rational choices by adjusting the perceived functional benefits of the channel when that channel is used for service transactions.

The use of consumer credit by Chinese citizens has risen rapidly in the Internet era. The purpose of this paper is to predict a mechanism for credit consumption through Internet usage, with social comparison and materialism as mediators. Four types of Internet usage (social use, entertainment use, informational use, and online shopping) were identified to investigate whether different types of Internet usage influence credit consumption differently and whether the influencing mechanisms vary.

A structured online survey involving 558 valid responses from Chinese college students was completed, with structural equation modeling being applied to analyze the collected data.

Among the four types of Internet activities, online shopping was found to be the most significant predictor of credit consumption; results show that it influences credit consumption through two indirect pathways: materialism and a combination of social comparison and materialism. Social use was found to only affect credit consumption through materialism. In contrast, the influences of both informational use and entertainment use on credit consumption were insignificant.

By testing the concurrent mediating effects of social comparison and materialism, this study broadens our understanding of how Internet usage and credit consumption are connected. While most studies empirically test overall Internet usage and focus on direct relationships, we identify four types of Internet activities and demonstrate the mechanisms by which different types of Internet usage influence credit consumption, and how consumption varies based on Internet activity.

Pipe cooling is an important measure for controlling the temperature in mass concrete. Since the temperature field in mass concrete containing cooling pipes is unsteady and three‐dimensional, and there are huge quantities of the cooling pipes in the concrete, the study of efficient and reliable algorithm is crucial. The purpose of this paper is to develop the composite element method (CEM) for the temperature field in mass concrete containing cooling pipes.

Each cooling pipe segment is looked at as a special sub‐element having definite thermal characteristics, which is located explicitly within the composite element. By the variational principle, the governing equation for the composite element containing cooling pipes is established.

One of the remarkable advantages of the method proposed is that each cooling pipe can be simulated explicitly while the difficulty of mesh generation around cooling pipes can be avoided.

The paper demonstrates how composite elements containing cooling pipes are degenerated to the conventional finite elements automatically when the first stage artificial cooling finished, and conversely, the conventional finite elements can also be transformed to the composite elements automatically when the second stage artificial cooling started. The comparison of the numerical example using FEM and CEM shows the rationality of the proposed method.

This study aims to propose a model-free statistic that tests asymmetric correlations of stock returns, in which stocks move more often with the market when the market goes down than when it goes up, and then empirically analyze the asymmetric correlations of the China stock market and international stock markets, respectively.

Using empirical likelihood method, this study designs and conducts a model-free test, which converges to χ2 distribution under regulated conditions and performs well in the finite sample using bootstrap critical value method.

By analyzing the authors' model-free test, the authors find that compared with Hong et al.'s test that closely relates to the authors, both of the tests are under rejected using asymptotic critical value. However, using the bootstrap critical value method can greatly improve the performance of the two tests. Second, investigating the power of the two tests, the authors find that the proportion of rejections of the authors' test is roughly 10-20 percent larger than Hong et al.'s test in mixed copula model setting. The last finding is the authors find evidence of asymmetric for small-cap size portfolios, but no evidence for middle-cap and large-cap size portfolios in the China stock market. Besides, the authors test asymmetric correlations between the USA and Japan, France and the UK; the asymmetric phenomenon exists in international stock markets, which is similar to Longin and Solnik's findings, but they are not significant according to both the authors' test and Hong et al.'s test.

The findings in this study suggest that both the authors' test and Hong et al.'s test are under rejected using asymptotic critical value. When applying these statistics to test asymmetric correlations, the authors should take care with the choice of critical value.

The empirical analysis has a significant practical implication for asset allocation, asset pricing and risk management fields.

This study constructs a model-free statistic to test asymmetric correlations using empirical likelihood method for the first time and corrects the size performance by bootstrap method, which improves the performance of Hong et al.'s test. To the authors' knowledge, this is the first study to test the asymmetric correlations in the China stock market.