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The purpose of this paper is to propose a new aerodynamic parameter estimation methodology based on neural network and output error method, while the output error method is improved based on particle swarm algorithm.

Firstly, the algorithm approximates the dynamic characteristics of aircraft based on feedforward neural network. Neural network is trained by extreme learning machine, and the trained network can predict the aircraft response at (k + 1)th instant given the measured flight data at kth instant. Secondly, particle swarm optimization is used to enhance the convergence of Levenberg–Marquardt (LM) algorithm, and the improved LM method is used to substitute for the Gauss Newton algorithm in output error method. Finally, the trained neural network is combined with the improved output error method to estimate aerodynamic derivatives.

Neither depending on the initial guess of the parameters to be estimated nor requiring numerical integration of the aircraft motion equation, the proposed algorithm can be used for unstable aircraft and is successfully applied to extract aerodynamic derivatives from both simulated and real flight data.

The proposed method requires iterative calculation and can only identify parameters offline.

The proposed method is successfully applied to estimate aircraft aerodynamic parameters and can also be used as a new algorithm for other optimization problems.

In this study, the output error method is improved to reduce the dependence on the initial value of parameters and expand its application scope. It is applied in aircraft aerodynamic parameter identification together with neural network.

Nanoparticles as the grease additives play an important role in anti-wear and friction-reducing property during the mechanical operation. To improve the lubrication action of grease, the tribological behavior of lithium-based greases with single (nanometer Al₂O₃ or nanometer ZnO) and composite additives (Al₂O₃–ZnO nanoparticles) were investigated in this paper.

The morphology and microstructure of nanoparticles were characterized by means of transmission electron microscope and X-ray diffraction. Tribological properties of different nanoparticles as additives in lithium-based greases were evaluated using a universal friction and wear testing machine. In addition, the friction coefficient (COF) and wear scar diameter were analyzed. The surface morphology and element overlay of the worn steel surface were analyzed by scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS), respectively.

The results show that the greases with nanometer Al₂O₃ or nanometer ZnO and the composite nanoparticles additives both exhibit lower COFs and wear scar diameters than those of base grease. And the grease with Al₂O₃–ZnO composite nanoparticles possesses much lower COF and shows much better wear resistance than greases with single additives. When the additives contents are 0.4 Wt.% Al₂O₃ and 0.6 Wt.% ZnO, the composite nanoparticles-based grease exhibits the lowest mean COF (0.04) and wear scar diameter (0.65 mm), which is about 160% and 28% lower than those of base grease, respectively.

The main innovative thought of this work lies in dealing with the grease using single or composite nanoparticles. And through a serial contrast experiments, the anti-wear and friction-reducing property with different nanoparticles additives in lithium grease are evaluated.

This study aims to investigate the impact of indium (In) content on the thermal properties, microstructure and mechanical properties of Sn-3Ag-3Sb-xIn (x = 0, 1, 2, 3, 4, 5 Wt.%) solders to enhance the performance of tin-based solder under demanding conditions and to meet the urgent need for high-reliability microelectronic interconnection materials in emerging sectors such as automotive intelligent technology, 5G communication technology and high-performance computing.

In this study, Sn-3Ag-3Sb-xIn solder alloys were prepared. The thermal properties of the solder alloys were characterised by differential scanning calorimetry. Subsequently, optical microscopy, scanning electron microscopy, X-ray diffraction and an electron probe X-ray microanalyser were used to analyse the influence of the In content on the microstructure of the solder. The mechanical properties of solder alloys were determined through tensile testing.

As the In content increased, the melting temperature of the Sn-3Ag-3Sb-xIn solder decreased, accompanied by less nucleation undercooling and an expanded melting range. The incorporation of In led to an enhancement in the yield and tensile strengths of the Sn-3Ag-3Sb-xIn solder alloys, but with a concomitant decrease in plasticity. In comparison to commercial Sn-3.0Ag-0.5Cu solder alloys, the yield strength and tensile strength of the Sn-3Ag-3Sb-3In alloy increased by 8.64 and 21.69 MPa, respectively, while the elongation decreased by 11.48%.

Sn-3Ag-3Sb-3In solder alloy was the most appropriate and expected comprehensive properties. The enhancements will provide substantial assistance and precise data references for the interconnection requirements in high-strength interconnection fields, such as automotive intelligent technology, 5G communication technology and high-performance computing.

The reliability of solder joints is closely related to the growth of an intermetallic compound (IMC) layer between the lead-free solder and substrate interface. This paper aims to investigate the growth behavior of the interfacial IMC layer during isothermal aging at 125°C for Sn-3Ag-3Sb-xIn/Cu (x = 0, 1, 2, 3, 4, 5 Wt.%) solder joints with different In contents and commercial Sn-3Ag-0.5Cu/Cu solder joints.

In this paper, Sn-3Ag-3Sb-xIn/Cu (x = 0, 1, 2, 3, 4, 5 Wt.%) and commercial Sn-3Ag-0.5Cu/Cu solder were prepared for bonding Cu substrate. Then these samples were subjected to isothermal aging for 0, 2, 8, 14, 25 and 45 days. Scanning electron microscopy and transmission electron microscopy were used to analyze the soldering interface reaction and the difference in IMC growth behavior during the isothermal aging process.

When the concentration of In in the Sn-3Ag-3Sb-xIn/Cu solder joints exceeded 2 Wt.%, a substantial amount of InSb particles were produced. These particles acted as a diffusion barrier, impeding the growth of the IMC layer at the interface. The growth of the Cu₃Sn layer during the aging process was strongly correlated with the presence of In. The growth rate of the Cu₃Sn layer was significantly reduced when the In concentration exceeded 3 Wt.%.

The addition of In promotes the formation of InSb particles in Sn-3Ag-3Sb-xIn/Cu solder joints. These particles limit the growth of the total IMC layer, while a higher In content also slows the growth of the Cu₃Sn layer. This study is significant for designing alloy compositions for new high-reliability solders.

The purpose of this paper is to analyze the reasons that plagiarism in online literature is so hard to control in China, and it will conclude with a clear solution for the future.

This paper begins its research with the statistics and analysis of plagiarism data and a review of expert interviews regarding online literature publishing. All of these data materials were collected from anti-plagiarism platforms, online literature websites, news report websites and judiciary office websites.

The paper provides empirical insights into why the plagiarism is so rampant in the publishing of online literature in China. It suggests that the current task of controlling network literature plagiarism is arguably created by the literary production platform, which leads to the problem of the validity of the “self-monitoring model.” In fact, controlling plagiarism must be emphasized by means of external monitoring, because strict supervision and various external punitive measurements for committing plagiarism can force literature-generating platforms to strengthen their own internal monitoring.

Online plagiarism occurs almost constantly, but it rarely results in court cases over copyright because of the lack of a robust copyright ecology in China. This paper considers large amounts of data and cases from self-publishing media platforms.

The paper includes implications for the development of plagiarism management in online literature publishing from the publishing Association, media and government.

This paper suggests to online literature users that plagiarism will be controlled when certain active measures against it are taken. The authors hope that this view will promote the development of original online literature.

This paper points out that China must strengthen supervision that comes from outside the online literature generate platforms to control the current rampant plagiarism that occurs on these platforms.

The purpose of this paper is to investigate factors influencing intent to adopt unmanned aerial vehicles for use in agricultural operations in Jilin Province, China.

This paper uses probit analysis to estimate the influence of factors on intent to adopt unmanned aerial vehicles for plant protection application operations in Jilin Province, China based on the Technology Acceptance Model.

UAV technology is acceptable to most participating farmers. Gender (male), agricultural income ratio, understanding of new technology, perceived ease-of-use and perceived usefulness have a positive relationship with farmers’ willingness to adopt UAVs.

For application, crop monitoring and other farm operations, UAVs have clear advantages. There remain challenges associated with the development of applicable technology and facilitating adoption among farmers. Understanding factors affecting adoption will contribute to the latter, and brings forth the following recommendations: conduct research on the cost effectiveness of UAVs for agriculture; accelerate development of the information service system; and increase financial support.

This paper is among the first to consider adoption intent among Chinese farmers of use of UAVs for agricultural operations.

The purpose of this paper is to investigate factors affecting use of microcredit among farmers in Northern China.

A two-stage Heckman model is used to estimate the effect of farmer and family characteristics and loan and lending environment on likelihood of farmer participation in microcredit and the value of loans taken. Data from 342 first-hand observations in Northern China were used.

Social capital, production cost, non-labor family members, income, guarantee group membership, village head loan guarantee, and messenger use were found to increase use of microcredit. The same factors were found to affect the value of loans among participating farmers except a guarantor requirement for the loan replaces membership in a guarantee group.

Results support that there is demand for microcredit among farmers and that they are willing to take steps to obtain it including seeking membership in a household guarantee group. Identification of faced constraints facilitates understanding of supply-side efforts with potential to decrease financial exclusion with a focus on external-to-market intervention.

Pivotal findings are the importance of guarantee group membership for loan approval and that this requirement hinders farmers’ ability to obtain credit. Three alternatives are suggested to overcome this constraint including excluding low-risk borrowers from a group guarantee requirement; charging higher interest rates on high risk loans not supported by a guarantee; and development of insurance options to replace the guarantee.

The purpose of this study was to investigate the effect of perceived corporate hypocrisy on customer mistreatment behaviors within the banking industry and the moderating effects of customer–company identification (CCI) and brand equity on the hypocrisy-mistreatment behavior relationship.

Using multistage sampling, 567 South Korean banking service users participated in an online survey. Structural equation modeling (confirmatory factor analysis) and hierarchical regression analysis were used to analyze the data.

Perceived corporate hypocrisy was positively related to customer mistreatment behaviors. CCI and brand equity differentially moderated the positive relationship between perceived corporate hypocrisy and customer mistreatment behaviors. Specifically, CCI and brand equity strengthened and weakened the positive relationship between perceived corporate hypocrisy and customer mistreatment behaviors, respectively.

Marketers and banking service managers should pay careful attention to customer evaluations of their social activities and communication about the ethical values and actions of their firms. Since CCI and brand equity have contrasting moderating effects on the corporate hypocrisy-aggressive behavior relationship, marketers should devise different strategies to manage the adverse effects of such corporate crises on company-identified and brand-committed customers. For example, managers should focus on customers who actively express their deep sense of disappointment or profound anger in response to corporate hypocrisy (e.g. those with high levels of CCI) because they are likely to exhibit aggressive behaviors toward the company or its employees. Managers need to devise customized relationship-recovery strategies for such customers (e.g. forging a personal connection between the customer and service provider).

The present findings delineate the adverse effects of perceived corporate hypocrisy on customer behaviors and the moderating effect of customer relationship quality on the corporate hypocrisy-mistreatment behavior relationship within the banking industry.

The purpose of this paper is to discuss the evolution of the food traceability system in China, examine factors that affect consumers' perception of a food traceability system, and determine their willingness to pay for having the system.

Beijing, one of the largest pork markets in urban China, was chosen and 400 consumers were randomly interviewed using questionnaires and finally a logistic model was employed to analyze consumers' willingness to pay for traceable pork.

The authors found that consumers' perception of pork traceability system is subject to a comparatively low level. Purchasing of traceable pork is affected by gender, self‐evaluation of health, awareness of the traceability system, concern about food safety, and the stochastic price willing to pay.

The paper is the first to quantify Chinese consumers' valuation for traceable pork and it helps pork producers and marketers understand consumers' willingness to pay a small premium of 4.5 RMB/kg (0.7 USD) for traceable pork. This finding has imperative policy implications that could help the government deal with the high cost associated with the use of a pork traceability system.

The purpose of this paper is to identify factors that affect farm acceptance of the new seeds. This paper develops a Bivariate Probit model with adjusted sample selection bias to analyze Chinese farmers' sequential decision‐making process in their adoption of plant new varieties (new seeds) under the new Variety Property Right Protection System.

Face‐to‐face interviews with farm households in 22 provinces were used to gather questionnaire information. A total of 341 surveys were collected and analyzed using a Bivariate Probit model adjusted for sample selection bias problems. Descriptive statistics for each selected variable used in the model are also presented.

This study concluded that farm location, land size, farm perceived dealer reputation, and farmer‐to‐farmer word‐of‐mouth information were found to be important factors that affect farm adoption of new seeds.

This study is based on first‐hand survey information collected by the researchers. Thus, the results are original and were not published elsewhere.