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Hydro-viscous drive (HVD) clutches are widely used in equipment requiring soft start, such as fans and pumps, to transmit torque and adjust speed by changing the gap distance between friction pairs. This paper aims to propose a novel two-parameter evaluation method for HVD during the mixed lubrication stage. The objective is to develop an effective model that establishes the relationship between these parameters and the actual surface topography.

In the presented methods, the fractal features of the real manufacturing surface are calculated based on the power spectrum function by the ultra-depth three-dimensional microscope. After that, the hybrid friction model of the friction plate is established based on mixed elasto-hydrodynamic lubrication theory, boundary friction model and fractal theory. Then the torque and load bearing characteristics of the clutch are obtained, and the influences of the surface fractal features are investigated and discussed. Finally, the Weierstrass–Mandelbrot function is adopted for the surface topography characterization and evaluation.

The results indicate that the proposed method exhibits good accuracy, while the speed difference between the friction pair exceeds 2,500 rpm. It is concluded that this paper proposed a way to evaluate the torque and loading capacity of HVD considering the real manufacturing surface topography and is helpful for surface optimization.

The originality and value of this study lie in its development of a novel torque and load bearing capacity evaluation method for HVD in mixed lubrication stage, considering manufacturing surface topography and describing the real manufacturing surface.

Combined defects in ball bearings may be caused during the use or manufacturing process, which can significantly affect their vibration characteristics. The previous defect models in the literature can only describe single defects such as the surface waviness and localized defect. This paper aims to propose an in-depth understanding of radial vibrations of a ball bearing with the combined defect.

A dynamic model for a ball bearing with the combined defect including the surface waviness and localized defect on its races is proposed. The effects of the combined defect sizes on the radial bearing vibrations are investigated. The results from the proposed model considering the combined defect are compared with the available results from the previous methods considering the single defects.

The acceleration amplitude is significantly affected by the surface waviness, localized defect and the combined defect on its races. The effect of the combined defect on the acceleration amplitude is larger than that of the single defect. The amplitude and peak frequency of the spectrum of acceleration for the combined defect increases with the defect sizes. The RMS value of the accelerations for the combined defect increases with the combined defect sizes.

Consequently, the proposed model can predict more accurate and in-depth understanding of the radial vibrations caused by the combined defect in the ball bearing.

China is currently constructing the public cultural service system on a national scale. Library strategic environment problems, such as the status of library in the public cultural service system, the relationship with relevant public cultural service institutions/organizations, and the factors influencing library development, etc., which increasingly raise people’s concern. The purpose of this paper is to solve above mentioned problems.

This paper used online and offline questionnaires to solicit feedback from public cultural service institutions/organizations. Based on the data from questionnaires, this paper analyzed library strategic environment in the public cultural service system in mainland China by adopting correlation analysis, mean analysis and factor analysis, etc.

Stakeholders (relevant public cultural service institutions) highly valued the status of library and no respondents believed that library did not belong to the public cultural service system. Compared with competing relationship between enterprises, library and relevant cultural services institutions were partners rather than competitors. Three main factors that influenced library strategic planning were identified: internal conditions factors, external environment factors and stakeholder related factors.

There are some limitations of this thesis. For instance, the sample size is not large enough and respondents are confined to cities, which may reduce the generalizability of the findings.

Through this analysis, library can learn more of national cultural environment in China, and take necessary measures to cope with these changes.

Labour relations management, business management, HRM, focusing on the labour relations of Chinese enterprises.

This case is designed for students in schools of business or management, undergraduate MBA or executive MBA classes. Students should already have a basic knowledge about Chinese labour relations, HRM, and organizational development.

In 2004, a deal transformed Anhui Xuanjiu Group from a state-owned enterprise (SOE) to a private company. Li Jian, the Chairman of Xuanjiu Group, focused on creating happiness for employees. Thanks to Li Jian's efforts, Xuanjiu emrged from its crisis which was formed in the planned economy system. After several years of development, the labour relations management of Anhui Xuanjiu Group became a model among private enterprises in China.

Students can gain new insights into labour relations in China. The case provides an example of building friendly labour relations to avoid labour disputes. It provides a set of measures for retaining and motivating workers.

Teaching notes are available for educators only. Please contact your library to gain login details or email support@emeraldinsight.com to request teaching notes.

The purpose of this paper is to propose a new algorithm for independent navigation of unmanned aerial vehicle path planning with fast and stable performance, which is based on pigeon-inspired optimization (PIO) and quantum entanglement (QE) theory.

A biomimetic swarm intelligent optimization of PIO is inspired by the natural behavior of homing pigeons. In this paper, the model of QEPIO is devised according to the merging optimization of basic PIO algorithm and dynamics of QE in a two-qubit XXZ Heisenberg System.

Comparative experimental results with genetic algorithm, particle swarm optimization and traditional PIO algorithm are given to show the convergence velocity and robustness of our proposed QEPIO algorithm.

The QEPIO algorithm hold broad adoption prospects because of no reliance on INS, both on military affairs and market place.

This research is adopted to solve path planning problems with a new aspect of quantum effect applied in parameters designing for the model with the respective of unmanned aerial vehicle path planning.

The purpose of this paper is to propose a biological edge detection approach for aircraft such as unmanned combat air vehicle (UCAV), with the objective of making the UCAV recognize targets, especially in complex noisy environment.

The hybrid model of saliency-based visual attention and artificial bee colony (ABC) algorithm is established for edge detection of UCAV. Visual attention can extract the region of interesting objects, and this approach can narrow the searching region for object segmentation, which can reduce the computational complexity. An improved ABC algorithm is applied in edge detection of the salient region.

This work improved ABC algorithm by modifying the search strategy and adding some limits, so that it can be applied to edge detection problem. A hybrid model of saliency-based visual attention and ABC algorithm is developed. Experimental results demonstrated the feasibility and effectiveness of the proposed method: it can guarantee efficient target localization, with accurate edge detection in complex noisy environment.

The biological edge detection model developed in this paper can be easily applied to practice and can steer the UCAV during target recognition, which will considerably increase the autonomy of the UCAV.

A hybrid model of saliency-based visual attention and ABC algorithm is proposed for biological edge detection. An improved ABC algorithm is applied in edge detection of the salient region.