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The shock absorber is an important component of vehicle suspension that attenuates the vehicle vibration. Its running state directly affects the performance of the vehicle suspension. The purpose of this paper is to quantitatively study the relationship between damping characteristics and air chamber and oil properties in single-tube pneumatic shock absorber.

Combined with the principle of fluid dynamics and hydraulic transmission technology, the rebound stroke and compression stroke mathematical models, and damping characteristics simulation model are established to investigate the effect of the air chamber and oil property on damping characteristics.

Research results show that the initial pressure of the air chamber is the key parameter which influences the damping characteristics of the shock absorber. The change of the initial pressure has more impact on damping force, and less impact on the speed characteristic; the initial volume of the air chamber almost has no effect on the damping characteristics. The density and viscosity of the oil have certain influence on the damping characteristics. Therefore, selecting suitable damping oil is very important.

Using Matlab/Simulink software to build simulation models, its results are very accurate. The conclusions can provide a theoretical reference for the structure design of a single-tube pneumatic shock absorber.

The purpose of this paper is to study the influence rules of geometric parameters on deformation of valve slices.

Based on the theory of flexural deformation of elastic thin slice, differential functions of deformation for both single and multi-slices are given and derived in detail. Furthermore, the effects of geometric dimensions on deformation are analyzed particularly by using Matlab/simulink.

The results indicated that the deformation decreases with the increment of fixed ring radius r_a, slice thickness h, and its number n. Meanwhile, the deformation increases with a rise of slice radius r_b, throttle position r_k, the radius ratio λ₁ and thickness ratio λ₂ of slices.

This research can provide some theoretical supports for the parametric and optimal design of adjustable damping shock absorber.

To better understand factors that lead to business model innovation (BMI) in organizations, this study argues that inclusive leadership is the primary source that motivates employee engagement in boundary-spanning activities, which fosters BMI by generating and integrating employee knowledge through boundary-spanning exploration.

This paper analyzes the relationships between inclusive leadership, boundary-spanning exploration and BMI to discover how they influence each other. This is achieved by a survey of more than 30 enterprises in Zhejiang Province, China. The survey data are analyzed using SPSS.

Inclusive leaders who display characteristics of openness, accessibility and availability have a positive effect on BMI and boundary-spanning exploration; openness and accessibility have more significant positive effect on BMI and boundary-spanning exploration.

Because this study covers only in Zhejiang Province, in China, the findings may not be easily generalizable to other contexts. Other factors, such as organizational structure and contextual characteristics, could also be added as antecedents in a future investigation. Moreover, the scales could be revised more suitable for China in the future.

The empirical findings can be used as guidelines for firms seeking to take advantage of inclusive leadership and to help firms motivate their employees to engage in boundary-spanning exploration to acquire, generate and integrate knowledge from diverse sources to promote BMI.

This study provides insights that will be of value by adding to the theoretical foundation of our understanding of the antecedents to firms' BMI. This study argues that employees' boundary-spanning exploration is important to BMI as well. Inclusive leadership is crucial to stimulate boundary-spanning exploration by employees. Therefore, how to encourage inclusive leadership in firms is well worth examining.

The purpose of this paper is to study a fractional grey model FAGM(1,1,t^α) based on the GM(1,1,t^α) model and the fractional accumulated generating operation, and then predict the national health expenditure, the government health expenditure and the out-of-pocket health expenditure of China.

The presented univariate grey model is systematically studied by using the grey modelling technique, the fractional accumulated generating operation and the trapezoid approximation formula of definite integral. The optimal system parameters r and α are evaluated by the particle swarm optimisation algorithm.

The expressions of the time response function and the restored values of this model are derived. The GM(1,1), NGM(1,1,k,c) and GM(1,1,t^α) models are particular cases of the FAGM(1,1,t^α) model with deterministic r and α. Compared with other forecasting models, the results of the FAGM(1,1,t^α) model have higher precision.

The superiority of the new model has high potential to be used in the medicine and health fields and others. Results can provide a guideline for government decision making.

The univariate fractional grey model FAGM (1,1,t^α) successfully studies the China’s health expenditure.

The purpose of this paper is to improve the hydraulic efficiency without changing the overall dimension. The blade profile optimization design of the aero-centrifugal pump based on the biharmonic equation surrogate model has been studied.

First of all, Bezier curves and linear function are used to control the annular angle distribution and the stacking angle of blade profile under the MATLAB platform. Grid independence analysis has been studied to find the finest mesh scheme. After the precision comparison of test data and computation fluid dynamics 15 sets of design parameters are carried out as the boundary condition of the biharmonic equation. The efficiency surrogate model of the biharmonic equation is constructed via iteratively solving of a discrete difference equation. The other two surrogate models of response surface model (RSM) and radial basis function neural network surrogate model (RBFNNSM) are compared with the biharmonic equation surrogate model by the standard of modified complex correlation coefficient R² and root mean square deviation (RSME). Finally, the artificial fish swarm algorithm has been used to find the global optimal design parameters with the objective function of highest efficiency.

The results show that the design parameters code conversion method can reduce the number of optimization parameters from five to three, makes the design space become a cube, and compared with RSM and RBFNNSM, the biharmonic equation surrogate model has higher precision with R² is 0.8958, RSME is 0.1382. The final optimum result of AFSA is at the point of [1 −1 −1]. The internal flow field analysis shows that after optimization the outlet relative velocity becomes more uniform and the wake effect has been significantly decreased. The hydraulic efficiency of the optimized pump is about 59.45 per cent increasing 5.4 per cent compared with a prototype pump.

This study developed a new method to optimize the design parameters of aero-centrifugal pump impeller based on biharmonic equation surrogate model, which had a good agreement with experimental values within just 15 sets of the original design. The optimization results shows that the method can improve the hydraulic efficiency significantly.

This paper aims to focus on how political resources and their correlation with business models affected the headquarters location decision making of successful private enterprises established in small cities.

The paper constructed a research model which included political resources and a business model as contributing factors; selected eight companies as the research object; and used cross‐case study method to explore the function of political resources and a business model to the headquarters location decision of private enterprises.

The special political environment during China's economic transformation created substantially different political resources between different regions and governments at different levels, which forced private enterprises to relocate their headquarters in order to chase political resources conveniently. The relevance of a business model and political resources determined the significantly different ways that private enterprises obtained political resources: enterprises which were highly dependent on local political resources found it difficult to make a decision regarding corporate headquarters relocation; those enterprises with a high political resources optimization capability would be driven by the pursuit of political resources to make their headquarters relocation decision; those enterprises with an inconspicuous connection between political resources and a business model would rather be “hermits” in a metropolis and relocate their headquarters.

This paper's research results would be conducive to further study of private enterprises' headquarters location decision making during China's economic transformation.

The paper indicates the importance of political resources and the relevance of corporate business models to the headquarters location decision of private enterprises; the paper further makes clear the status of political resources as an important factor in location theory.

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

China’s swift economic rise, as symbolized by the first Chinese Olympics and by surpassing Japan to become the world’s second largest economy despite the recent global financial meltdown, has been accompanied by a transformation of Chinese foreign policy behavior. After spending the last decade emphasizing China’s “peaceful rise” or “peaceful development,” Beijing has begun to expound its policy preferences and territorial claims more forthrightly, even assertively. The purpose of this chapter will be to consider the origins, consequences, and likely future of the new Chinese foreign policy in the wake of the leadership transition at the 18th Party Congress in 2012 and the 12th National People’s Congress in 2013.

This paper aims to identify the relationships of both organizational isomorphism and knowledge search with the innovation performance of cluster enterprises. It also specifies the mechanism by which organizational isomorphism affects innovation performance, through knowledge search.

Firm-level data were collected with questionnaires distributed to cluster enterprises in Zhejiang Province, China, which produced 165 usable responses for the analysis. Both multiple regression analyses and structural equation modelling were used to test the hypotheses.

Normative isomorphism and mimetic isomorphism have inverse U-shaped effects on the innovation performance of cluster enterprises, as does exploratory knowledge search. Exploitative knowledge search and the balance between two types of knowledge search have positive effects on the innovation performance of cluster enterprises; exploratory and exploitative knowledge searches exert partial mediation effects between the organizational isomorphism and innovation performance of cluster enterprises. The mediating effect of knowledge search transforms the inverse U-shaped effect of normative isomorphism and mimetic isomorphism on innovation performance into a positive effect.

This study provides new insights into the effects of organizational isomorphism on innovation performance by showing the indirect influence of organizational isomorphism in clusters. The study proposes a strategic logic of moderate isomorphism, clarifies the innovative effect of different knowledge search modes and reveals the construction and management mechanisms of organizational isomorphism and knowledge search strategy of firms in clusters.