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The purpose of this paper is to investigate the effect of thermal‐oxidative aging at 150°C on the mechanical properties of carbon fibre reinforced bismaleimide composites.

Composites specimens after thermo‐oxidative aging at 150°C for various times (up to 1,000 h) were investigated by scanning electron microscopy (SEM) for fracture morphology, Fourier transform infrared (FTIR) spectroscopy for chemical structures, and flexural strength test and inter‐laminar shear strength (ILSS) test for mechanical properties.

The results indicated that the mechanical properties of carbon fibre/BMI composites were affected significantly by testing temperature rather than by aging time. SEM results showed that the good adhesion of fibre and matrix resulted in the better mechanical properties. The composites showed lower flexural strength and ILSS at 150°C due to the viscoelastic behaviour of matrix resin. The FTIR spectra confirmed the decomposition of crosslinked maleimide occurred just on the surface of composites during various aging times.

Results indicated that carbon fibre/BMI composites had excellent heat resistance and aging resistance.

Due to their excellent thermal and mechanical properties, the carbon fibre/BMI composites show greater potential for their applications in some extreme fields such as aerospace and machine.

The paper investigates the relationships of the fracture morphologies of composites and chemical structures of matrix resin to the mechanical properties after thermo‐oxidative aging.

Weather affects consumer decision-making. However, academic research on how weather factors affect specific takeaway foods is limited. This paper aims to fill in the gap and therefore to contribute to online marketing and operation.

Web crawler techniques were first exploited to collect takeaway food ordering data from Meituan, the world’s largest GMV platform. Then statistics models and a time series regression model were selected to study the weather impact on online orders.

The findings highlight that certain weather factors, such as temperature, air quality and rainfall have clear effects on most category takeaway orders.

Quantitative analysis of weather impacts on the takeaway ordering business will help to guide the online service platforms for marketing promotion and the settled businesses to make reasonable arrangements for inventory and marketing tactics.

Giant orthogonal grid barrel vault is generated by deleting members in the inessential force transfer path of the two-layer lattice barrel vault. Consisting of members in the essential transfer path only, giant orthogonal grid barrel vault is a new type of structure with clear mechanical behavior and efficient material utilization. The paper aims to discuss this issue.

The geometrical configuration of this structure is analyzed, and the geometrical modeling method is proposed. When necessary parameters are determined, such as the structural span, length, vault rise, longitudinal and lateral giant grid number and section height to top chord length ratio of the lattice member, the structure geometrical model can be generated.

Numerical models of giant orthogonal grid barrel vaults with different rise–span ratios are built using the member model that can simulate the pre-buckling and post-buckling behavior. So the possible member buckle-straighten process and the plastic hinge form–disappear process of the structure under strong earthquake can be simulated.

Seismic analysis results indicate that when the structure damages under strong earthquake there are a large number of buckling members and few endpoint plastic hinges in the structure. Dynamic damage of giant orthogonal grid barrel vault under strong earthquake is caused by buckling members that weaken the structural bearing capacity.

Anchored in the role of a social arbiter, the purpose of this study is to examine whether and how media coverage has an impact on CEO overconfidence and further explore how media ownership and Confucianism affect the relationship in the Chinese context.

Using a sample of 1,492 Chinese listed companies from 2010 to 2015, the study adopts random effects models to empirically analyze the effect of media coverage on CEO overconfidence and the roles of media ownership and Confucianism.

The paper finds that media coverage is significantly and positively associated with CEO overconfidence, and the positive relationship between media coverage and CEO overconfidence becomes stronger for state-controlled media. What is more, the influence of media coverage on CEO overconfidence is attenuated for those firms located in stronger Confucianism atmosphere. A further analysis reveals that different tenors of media coverage yield asymmetric effects.

The paper provides a new and solid support for the argument that media praise stimulates CEO overconfidence and increases the knowledge about under what conditions CEO overconfidence varies, broadly speaking which fosters the development of upper echelons theory (UET). Meanwhile, the results extend the literature on media effect and information processing. The findings are also beneficial to improve corporate decisions and government regulation on Chinese media systems.

With the rapid development of the sharing economy in manufacturing industries, manufacturers and the equipment suppliers frequently share capacity through the third-party platform. This paper aims to study influences of manufacturers sharing capacity on the supplier and to analyze whether the supplier shares capacity as well as its influences.

This paper deals with conditions that the supplier and manufacturers share capacity through the third-party platform, and the third-party platform competes with the supplier in equipment sales. Considering the heterogeneity of the manufacturer's earning of unit capacity usage and the production efficiency of manufacturer's usage strategies, this paper constructs capacity sharing game models. Then, model equilibrium results under different sharing scenarios are compared.

The results show that when the production or maintenance cost is high, manufacturers sharing capacity simultaneously benefits the supplier, the third-party platform and manufacturers with high earnings of unit capacity usage. When both the rental efficiency and the production cost are low, or both the rental efficiency and the production cost are high, the supplier simultaneously sells equipment and shares capacity. The supplier only sells equipment in other cases. When both the rental efficiency and the production cost are low, the supplier’s sharing capacity realizes the win-win-win situation for the supplier, the third-party platform and manufacturers with moderate earnings of unit capacity usage.

This paper innovatively examines supplier's selling and sharing decisions considering manufacturers sharing capacity. It extends the research on capacity sharing and is important to supplier's operational decisions.

Though China is taking many steps to offer affordable houses to the public, the gap between the demand and supply for such affordable houses is still huge. Rapidly growing demand for affordable housing has encouraged large Chinese cities, faced with housing imbalance, to invest in developing affordable properties. As a result, the Chinese central government has started to encourage local governments to use Public-Private Partnerships (PPPs) and private capital to supplement the funding deficit. There is also an on-going debate regarding the need to establish prerequisites for institutions to meet in order to achieve effective PPPs. In this paper, we examine what the current institutional environment is in China and how China is meeting these prerequisites for effective PPPs. We also examine the main programs on affordable housing and propose a potential field for using PPPs. We draw the conclusion that PPPs are more favorable for renting-oriented type projects than owning-oriented projects. In this context, the advantages of the PPP model for China's renting-oriented affordable housing programs are would be the provision of private financing, the enhancing efficiency by involving private sector experts and the statement of bundling constructions and maintenance and operation work in the contract, which motivates the private sector to build properties up to standard for its cost efficiency from the whole project perspective.

China is not only the biggest mutton consumer, but also the top mutton importer in the world. China’s urban households are becoming the key driving force behind a surge in mutton consumption. Therefore, the purpose of this paper is to investigate the determinants of mutton demand in urban China.

Based on a sample of 32,910 urban households across six provinces and autonomous regions, an inverse hyperbolic sine (IHS) double-hurdle model is estimated, by maximum likelihood estimation, to reveal the determinants of mutton consumption-at-home.

The empirical results indicate that, first, household income has a positive effect on mutton consumption, and higher income households have a higher income elasticity; second, wet weather increases probability, but reduces conditional level and unconditional level; finally, minority group households consume more mutton than Han group households.

It is necessary for policymakers to develop a long-term outlook in relation to the increase of China’s mutton appetite and to shift from a domestic perspective to a global one and develop diversified import strategies. Furthermore, policymakers require to make a practicable emergency preplan for tackling short-term agglomeration of demand for mutton, attributed to festivals, and religious events of a minority ethnic group.

This is a major work based on a large sample of 32,910 urban households conducted by the National Bureau of Statistics of China. This paper uses an IHS double-hurdle model to quantify the determinants of mutton consumption; it sheds light on the climatic, regional, and ethnic characteristics of mutton consumption in urban China.

This study aims to promote the anti-disturbance and tracking accuracy of optoelectronic stabilized platforms, which ensure that optical detectors accurately track targets and acquire high-quality images.

An improved active disturbance rejection control (ADRC) strategy based on model-assisted double extended state observers (MDESOs) is proposed in this paper. First, by establishing an auxiliary model, the total disturbances are separated into two parts: inner and external disturbances. Then, MDESOs are designed to estimate the two parts by separately using two parallel ESOs, by which the controlled plant is adjusted to the ideal pure integral series. Simultaneously, combined with the nonlinear state error feedback, an overall control strategy is established.

Compared with the conventional ADRC and proportional derivative, the improved ADRC (IADRC) has stronger robustness and adaptability and effectively reduces the requirements for model accuracy and the gain of the ESO. The error of the auxiliary model is tolerated to exceed 50%, and the parameter values of the MDESOs are reduced by 90%.

The total disturbance rejection rate of the proposed strategy is only 3.11% under multiple disturbances, which indicates that the IADRC strategy significantly promotes anti-disturbance performance.

This study aims to evaluate enterprise technology innovation capability in prefabricated construction (PC) from an input-output perspective, using six integrated enterprises in China as cases.

An evaluation system for enterprise technology innovation capability in PC was constructed, including total input, technology output (TO) and project output. All the evaluation indexes were quantified, and the subject and object indexes weights were determined using the fuzzy cognitive map and information entropy, respectively. The final scores and ranks were evaluated through gray relational analysis (GRA) based on the combined weights.

It was found that enterprise technology innovation capability in PC was low in China, with its unbalanced development in different dimensions and the poorest performance in TO, currently.

This research has developed an evaluation system for technology innovation capability in PC at the enterprise level and scientifically quantified all the indexes, which is a breakthrough over existing studies. The GRA model based on the combined weights proposed in this study can be applied to other comparable fields and regions, with its easy operation.

Vehicle lightweight design has positive implications for reducing energy consumption and abating greenhouse gas emissions. The traditional trailer axle design mainly focuses on the overall performance of the trailer axle. Only when the local performance does not meet the requirements will local performance optimization be done, such as local heat treatment to improve local strength. Such a design results in an uneven distribution of axle performance and excess performance in some local structures. The purpose of this study is to investigate the weight reduction on the premise of ensuring the structural dimensions of the outer surface of the axle remain unchanged and the reliability of the axle.

The axle is parameterized by computer aided design, and the optimized axle finite element model based on computer aided engineering is established and verified by taking the eight dimensions of the axle cavity structure which affect the performance as parameters. A genetic algorithm is used to optimize the axle cavity structure size and axle weight based on multiobjective optimization, and eight optimized size parameters of axle cavity structure are obtained.

The total weight of the optimized axle of TM1314 is reduced by 10.2 kg, and the weight reduction ratio reaches 10.7%. According to the optimized structural size of the axle, the specimen was trial-manufactured, and the bench tests of stiffness, strength and fatigue life were carried out according to the test requirements of the trailer axle standard (JT/T 475-2002). The test results show that the maximum deformation of the specimen is 2.46 mm, the strength safety factor of the specimen body and the steel plate spring seat are 6.71 and 6.86 and bear the alternating load more than 1.05 × 106 times, which meets the standard of the trailer axle and is better than the original design requirements of the trailer axle.

In this study, the multiobjective optimization model of the axle is established, the response surface is constructed by the Latin hypercube sampling design method and the optimal solution set is obtained by the multiobjective genetic algorithm. It has been verified by bench tests that it can achieve a weight reduction of 10.7% under the premise of the same structure and size of the outer surface of the axle. The lightweight method based on multiobjective optimization proposed in this paper can provide a reference for the lightweight design of other key vehicle components.