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This study aims to improve the complexity of chaotic systems and the security accuracy of information encrypted transmission. Applying five-dimensional memristive Hopfield neural network (5D-HNN) to secure communication will greatly improve the confidentiality of signal transmission and greatly enhance the anticracking ability of the system.

Chaos masking: Chaos masking is the process of superimposing a message signal directly into a chaotic signal and masking the signal using the randomness of the chaotic output. Synchronous coupling: The coupled synchronization method first replicates the drive system to get the response system, and then adds the appropriate coupling term between the drive The synchronization error and the coupling term of the system will eventually converge to zero with time. The synchronization error and coupling term of the system will eventually converge to zero over time.

A 5D memristive neural network is obtained based on the original four-dimensional memristive neural network through the feedback control method. The system has five equations and contains infinite balance points. Compared with other systems, the 5D-HNN has rich dynamic behaviors, and the most unique feature is that it has multistable characteristics. First, its dissipation property, equilibrium point stability, bifurcation graph and Lyapunov exponent spectrum are analyzed to verify its chaotic state, and the system characteristics are more complex. Different dynamic characteristics can be obtained by adjusting the parameter k.

A new 5D memristive HNN is proposed and used in the secure communication

3D steady heat conduction analysis considering heat source is conducted on the fundamental of the fast multipole method (FMM)-accelerated line integration boundary element method (LIBEM).

Due to considering the heat source, domain integral is generated in the traditional heat conduction boundary integral equation (BIE), which will counteract the well-known merit of the BEM, namely, boundary-only discretization. To avoid volume discretization, the enhanced BEM, the LIBEM with dimension reduction property is introduced to transfer the domain integral into line integrals. Besides, owing to the unsatisfactory performance of the LIBEM when it comes to large-scale structures requiring massive computation, the FMM-accelerated LIBEM (FM-LIBEM) is proposed to improve the computation efficiency further.

Assuming N and M are the numbers of nodes and integral lines, respectively, the FM-LIBEM can reduce the time complexity from O(NM) to about O(N+ M), and a full discussion and verification of the advantage are done based on numerical examples under heat conduction.

(1) The LIBEM is applied to 3D heat conduction analysis with heat source. (2) The domain integrals can be transformed into boundary integrals with straight line integrals by the LIM. (3) A FM-LIBEM is proposed and can reduce the time complexity from O(NM) to O(N+ M). (4) The FM-LIBEM with high computational efficiency is exerted to solve 3D heat conduction analysis with heat source in massive computation successfully.

The purpose of this paper is to propose the complementary design rules, give a quantitative comparison and analyze the force production mechanism of two kinds of primary wound field flux-switching linear (PWFFSL) motors.

PWFFSL motors have the merits of no use of rare-earth magnet, low cost and a wide operation range in which the armature windings and the field windings are all located at the short primary mover and the secondary is very robust. Hence, the PWFFSL motor is ideal for rail transportation systems which need a long stator and a wide speed range. To overcome the disadvantages of the existing PWFFSL motors, new complementary design rules will be proposed. Also, to offer a better PWFFSL motor for the rail transportation systems, it is necessary to investigate different structures of PWFFSL motors and give a comprehensive comparison. To predict the force performance of two kinds of PWFFSL motors with different secondary types, their flux density analysis and force production mechanism will be presented and compared.

The comparison result shows that the PWFFSL motor with toothed secondary can offer larger thrust force, higher force density and higher efficiency, whereas the PWFFSL motor with segmented secondary has the merits of lower force ripple, less use of stator iron, higher power factor and less critical saturation.

Many PWFFSL motors with different primary/secondary pole pitches based on the proposed design principle have not been considered in this paper.

This paper has presented the air-gap flux analysis, proposed the complementary design rules for two kinds of PWFFSL motors with different secondary types and compared the electromagnetic performance of the two motors.

The purpose of this study is to introduce the top-level design ideas and the overall architecture of earthquake early-warning system for high speed railways in China, which is based on P-wave earthquake early-warning and multiple ways of rapid treatment.

The paper describes the key technologies that are involved in the development of the system, such as P-wave identification and earthquake early-warning, multi-source seismic information fusion and earthquake emergency treatment technologies. The paper also presents the test results of the system, which show that it has complete functions and its major performance indicators meet the design requirements.

The study demonstrates that the high speed railways earthquake early-warning system serves as an important technical tool for high speed railways to cope with the threat of earthquake to the operation safety. The key technical indicators of the system have excellent performance: The first report time of the P-wave is less than three seconds. From the first arrival of P-wave to the beginning of train braking, the total delay of onboard emergency treatment is 3.63 seconds under 95% probability. The average total delay for power failures triggered by substations is 3.3 seconds.

The paper provides a valuable reference for the research and development of earthquake early-warning system for high speed railways in other countries and regions. It also contributes to the earthquake prevention and disaster reduction efforts.

This paper aims to examine and analyze the effects of government policy, quality of human resources and professional institutions on workforce competitiveness using welding technology variable as a mediating variable.

This study used quantitative research by using partial least square – structural equation modeling (PLS-SEM) to analyze the collected data.

Based on the results of the analysis, it was noted that there was a significant influence between government policy, quality of human resources and professional institutions on welding technology. The coefficients are characterized by a positive direct relationship, which means that the higher the quality of government policy and human resources professionals variables, the higher the value of the institute of welding technology.

This study recommends that government should create policies that have benefits to competitiveness of Indonesian workforce. Implications from this study support government to use the model to determine and initiate policies in the field of welding as well as establish clear and standardized operating standards and recruitment process (government apparatus) that can accommodate the competitiveness of welding workers in Indonesia.

The originality of this paper is that the participatory approach was adopted in this study using PLS-SEM. In addition, this study was one of the first studies to carry out research at the BNSP office, BLK-Bandung-Jakarta, Makassar, B4T and dismiss the Ministry of Manpower and the Ministry of Industry in Jakarta, Indonesia, where there was no research in this location. Previous studies conducted research in various case studies.

The purpose of this paper is to analyze the evolution of Chinese technology policy, assess its technological and economic performance from the visual angle of “market in exchange for technology” strategy.

A quantified method based on policy contents from policy power, policy goals and policy means was developed to build a policy database, and analyze the evolutionary tendency of Chinese technology policy. In addition, econometric models were built to assess the performance of technology policy.

The critical goals of Chinese technology policy are introducing technology directly or indirectly by introducing foreign investment and innovation, but the critical linkage between introduction and innovation‐technology absorption was absent – almost all policy means aim at the introduction of foreign investment and innovation but not technology absorption. More unfortunately, the econometric results show that introduction of foreign investment contributes little, while technology absorption contributes much more. Institutional path‐dependence and the competition for benefits among different departments have aggravated an already unbalanced emphasis on technology policies during the reform.

During the quantification of technology policy, one perhaps loses some information about policy, and it can only be used to analyze the technology policy system, not special technology policy.

Analyses of the evolution of Chinese technology policy and econometric results show the blunder of “market in exchange for technology” strategy from policy formulation and execution. Also, it leads to the optimization of technology policy from policy targets, implements based on national technology and innovation strategy.

The paper develops the method of technology policy quantification and builds econometric models to assess the contribution of technology policy to technology progress and economy development.

The anticorrosion coatings used in marine and atmospheric environment are subjected to many environmental factors. And the aging failure has been puzzling researchers. The purpose of this study is to find the correlation between the initial aging of epoxy coatings and the typical marine atmospheric environmental factors.

The epoxy coatings were subjected to a one-year exposure in three typical marine atmospheres. Meanwhile, principal component analysis, linear regression and Spearman and gray correlation analysis were applied to quantify the environmental characteristics and establish correlations with the coating aging.

The results indicate that the coating will undergo macroscopic fading and chalking upon exposure to the marine atmosphere, while microscopic examination reveals holes, cracks and partial peeling. The adhesion performance and electrochemical properties of the coating deteriorated with prolonged exposure, coating aging mainly occurs with the generation of O-H bonds and the breakage of molecular chains such as C-N and C-O-C. The coating was most deeply aged after exposure to the Xisha, followed by Zhoushan and finally Qingdao. Environmental factors affect the photooxidative aging and hydrolytic degradation processes of coatings and thus coating aging. To further demonstrate the correlation between environmental factors and coating aging, principal component analysis was used. The correlation model between environmental factors and coating aging was subsequently obtained. The correlation model between the rate of coating adhesion loss (E) and the comprehensive evaluation parameter of environmental factors (Z) is expressed as E = 0.142 + 0.028Z. Meanwhile, the Spearman correlation analysis and gray correlation method were used to investigate the impact of each environmental factor on coating aging. Solar irradiation, relative humidity and wetting time have the highest correlation with coating aging, which are all above 0.8 and have the greatest influence on coating aging; wind speed and temperature have the smallest correlation with coating aging, which are about 0.6 and have the least influence on coating aging.

This paper establishes a correlation between typical marine environmental factors and coating aging performance, which is crucial for predicting the service life of other coatings in diverse environments.

As a result of the new reform of the college curriculum in China in 1998, the previously separated five information‐related majors were merged into a new special “information management and systems” curriculum. This change brings about both new challenges and new threats to the old information science specialism. However, it is inevitable for the specialism to change itself.

The purpose of this paper is to implement a comparative analysis on the evolution of technology policies of central and local governments in China and to uncover the relationship of technology policies.

A quantitative method based on policy contents from policy power, policy goals and policy instruments was developed to build a policy database and, taking Jiangsu province's policy practice as an example, was used to comparatively analyze the evolutionary process and the relationship of technology policies issued by central and local governments in China.

Comparative analysis shows that technology policies of central government are focused on the strategy of “Market in Exchange for Technology”. However, technology absorption as the critical part to realize the strategy was neglected due to the competition of interests among different agents. Local government has gradually developed a different technology development strategy to promote independent innovation on the basis of its better economic and science and technology conditions. So, the correlation coefficients of technology policies between central and local (Jiangsu) governments on policy power, policy instruments and policy goals have decreased continually.

Because of the limitation of data and time, this paper adopted quantification criteria on the contents of policies. Also, it is necessary to explore the coordination of technology policies between central and local governments.

Chinese technology policies should balance administrative rights reasonably between central and local governments and promote the coordination among the central authority, ministries, commissions, local governments and enterprises.

This paper has made a novel quantitative and comparative analysis about the relationship of technology policies between central and local (Jiangsu) governments.

The purpose of this paper is to analyze the coordination of Chinese technology policy and assess its contribution to technology progress and economy development.

A method was developed to assess the coordination and its tendency of technology policy based on technology policy quantification. In addition, econometric models were built to estimate performance of technology policy coordination.

Chinese technology policy coordination shows significant characteristics in different periods; the level of policy coordination is promoted rapidly because the institutional path‐dependence and the competition of benefits among departments have aggravated an already unbalanced emphasis on the wording of the technology policy during the process of economic and political reform. The coordination among departments, coordination of policy goals and coordination of policy means play different roles in technology progress and economy development.

Because of the limitation of data and time, the paper cannot assess the coordination among policy goals and policy means. Also, it is necessary to study the interaction of different principals and agencies during technology policy formulation and execution.

The methods in the paper can easily be used by decision makers evaluating the situation of technology policy coordination, and optimize policy based on the relationship of different policy targets and policy implements, especially the interaction of different principals and agencies.

The paper develops a method to assess technology policy coordination based on technology policy quantification and builds econometric models to assess its contribution to technology progress and economy development.