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To investigate transverse vibration of the eccentric rotor in a 12/8 poles switched reluctance motor (SRM), a transverse analytical vibration model is built by finite element method (FEM) under the interaction of radial magnetic resultant and vibration displacement. External forces, including radial magnetic resultant and centrifugal force, are also derived in detail, according to the variation of airgap and current and other intermediate parameters with rotation angle.

The transverse vibration response of the eccentric rotor including radial magnetic resultant and vibration displacement is solved by Newmark-β method, after inputting the currents of three phase windings under angle position control strategy. The basic characteristics of radial magnetic resultant and vibration displacement are reflected in time and frequency domain.

The magnetic resultant vector of the eccentric rotor presents multi-petals star geometric shape. The frequency distribution of magnetic resultant relates to rotation speed, current waveform and the least common multiple of the stator and rotor teeth. However, the frequency distribution of the vibration displacement also relates closely to the first-order critical whirl speed of the rotor. When the rotor is running at certain speeds, it will display superharmonic resonance and show abundant displacement locus.

By using this analytical model and solving process proposed in this paper, the nonlinear coupled vibration response of the eccentric rotor in SRM can be analyzed and discussed rapidly; only the stator’s winding currents obtained by experiment or electromagnetic simulation is needed as input.

This paper aims to propose a technical solution to rapidly access and locate the nearest interlibrary loan resources using OpenURL in the services of a local library.

First, the paper creates knowledge bases of “nearest access” services, which can automatically identify the nearest library and rapidly locate the resources in the target library. The knowledge bases consist of information about the nearby libraries and a rapid location rule for resources in these libraries. Second, the paper designs “nearest access” algorithms that allow users to identify and select the nearest interlibrary loan resources from the knowledge bases of “nearest access” services.

Through these steps, the paper establishes an architecture for accessing resources in the nearest library that are based on a combination of knowledge bases and “nearest access” algorithms, providing users with a convenient and rapid method to access interlibrary loan resources.

The innovation of this research lies in the ability of the proposed architecture in providing accurate, agile and personalized access to digital interlibrary loan services. Through this work, users will finally possess a tool to rapidly locate the resources in the nearest library using OpenURL.

This aim of this article is to propose a technical solution for digital libraries to establish the information needs ontology based on a comprehensive understanding of personalized user information needs and offer an information push service by really simple syndication (RSS) in a ubiquitous computing environment.

First, the authors formalize an ontology model applicable to the ubiquitous computing environment to describe user information needs comprehensively. The information needs related to the user's research activities are regarded as the ontology, which is described with web ontology language (OWL), and thus an ontology knowledgebase is established. Second, in light of the user's explicit information needs, the digital library finds the hidden information needs from the ontology knowledgebase, and also extracts the information resources required by the user from the corresponding database and then pushes them to the user by means of RSS. Finally, users can browse through a man‐machine interface to access the information.

After these steps, an RSS information push service architecture is established based on the user information needs ontology, providing the users with dynamic, personalized and proactive information services.

The innovation of this research lies in the fact that the architecture that is put forward is helpful to improve the accuracy and integrity of information push service of digital library, and is also beneficial for the research on u‐library.

Cities, like other ecosystems, are changing and evolving at a growing pace. Therefore, innovation has become a critical success factor in the creation of ‘smart cities’. A smart city is one that uses technology as a platform to serve its citizens’ needs and foster innovative processes that enhance their quality of life. In this chapter, the authors present two case studies of urban open innovation processes in, respectively, Haifa in Israel and Bremerhaven in Germany, which demonstrate the engagement of all stakeholders, motivated by passion, altruism and the desire to cooperate. The first case concerns open innovation with the young, and the second open innovation with the elderly. Both case studies demonstrate how passion led to altruism which encouraged citizens to volunteer to contribute and co-create a better future for all the city’s residents by enabling better communication among stakeholders in the context of a complex urban environment.

The buried pipe element method can be used to calculate the temperature of mass concrete through highly efficient computing. However, in this method, temperatures along cooling pipes and the convection coefficient of the cooling pipe boundary should be improved to achieve higher accuracy. Thus, there is a need to propose a method for improvement.

According to the principle of heat balance and the temperature gradient characteristics of concrete around cooling pipes, a method to calculate the water temperature along cooling pipes using the buried pipe element method is proposed in this study. By comparing the results of a discrete algorithm and the buried pipe element method, it was discovered that the convection coefficient of the cooling pipe boundary for the buried pipe element method is only related to the thermal conductivity of concrete; therefore, it can be calculated by inverse analysis.

The results show that the buried pipe element method can achieve the same accuracy as the discrete method and simulate the temperature field of mass concrete with cooling pipes efficiently and accurately.

This new method can improve the calculation accuracy of the embedded element method and make the calculation results more reasonable and reliable.

The purpose of this paper is to examine the relationship between bank diversity and small- and medium-sized enterprise (SME) firm innovation in China to evaluate the impact of recent bank deregulation.

Using a large data set that includes 8,143 firm-year observations of 1,122 listed SME firms in China and baseline and robustness regression analyses, the authors identify how bank diversity affects firm innovation and via what economic mechanisms. Potential endogeneity problems are considered and addressed in the design and analysis to minimize research bias.

The authors find robust evidence that bank diversity improves firm innovation. Specifically, the findings suggest that the positive effects of bank diversity on firm innovation are only significant for the firms which are more external finance dependent, have fewer growth opportunities and/or located in the provinces having low financial market development.

This study provides novel evidence and insights into the relationship between banking market structure and the determinants of firm innovation in the Chinese context, as a result of China’s banking deregulation.

The promotion of financial inclusion can disturb the composition of traditional bank concentration and change the relationship between bank concentration and the availability of small and medium-sized enterprise (SME) financing. This paper concentrates on a less frequently explored area of research by examining the relationships between bank concentration, financial inclusion and SME financing availability respectively, and the interaction between bank concentration and financial inclusion after the implementation of a financial inclusion strategy in China.

Using firm-level data from 1,509 listed SMEs in China from 2007 to 2017 and applying rigorous analyses, we identify how bank concentration affects SME financing availability under the promotion of financial inclusion and also the mechanisms involved.

We find that bank concentration and financial inclusion respectively have positive impacts on the credit available to listed SMEs, indicating that the promotion of financial inclusion in China has reached a new high watermark. The positive impact of bank concentration is reduced when the level of financial inclusion is high. Conversely, a higher level of financial inclusion favours SME credit availability at only a low degree of bank concentration. Our findings suggest that financial inclusion has a substitution effect on bank concentration and has enabled us to add new interpretations to relevant theories; namely, the Market Power and Information Theories respectively.

This study provides new insights into the relationship between bank concentration and SME finance availability under the promotion of financial inclusion.

The purpose of this paper is to investigate the evolution of the permeability of spherical packing during cold compaction by pore-scale modeling.

The discrete element method (DEM) is used to generate spherical packing structure under different compressive pressures and the Lattice Boltzmann method (LBM) is adopted to calculate the permeability of each spherical assembly.

It is found that the decrease of the porosity is the main reason of the reduction in permeability in the initial compression stage, but its influence becomes insufficient in the late compression stages. Besides, two empirical formulas are obtained, which describe the relation between the permeability and the equivalent mean diameter and the variation of normalized permeability with compressive pressure, respectively.

In this study, the authors study the spherical particles and ignore the non-spherical effects. Besides, the classical contact model, the linear-spring-damping model, is used in DEM, so the plastic deformation cannot be considered.

The DEM and the LBM are well combined to study the compaction effects on permeability of spherical packing. Two simple expressions of the spherical packing structure with uniform diameter distribution are given for the first time.

The purpose of this study is to solve the oil drill pipe joints and casing excessive wear problems and to improve the drill pipe joint-casing wear resistance and anti-friction properties.

On the surface of the drill pipe joints using oxyacetylene flame bead weld (BW) wear-resistant welding wire ARNCO-100XT^TM prepares welding layer, high-velocity oxygen fuel (HVOF) Cr₃C₂75-NiCr25 prepares coating and subsonic flame spray and remelt (SFSR) Ni60 prepares coating, then comparing and analyzing the friction and wear of the three types of wear-resistant layers and the casing under the condition of 1.8 g/cm³ mud drilling fluid lubrication. The wear resistance and anti-friction performance of the drill pipe joints were evaluated based on the wear situation, finally revealing its friction and wear mechanisms.

Three types of wear-resistant layers can improve the surface wear resistance of drill pipe joints, the wear-resistant layer and the substrate are well combined and the welding layers and coating are both dense and uniform. The wear resistance of the HVOF-Cr₃C₂75-NiCr25 coating is 10.9 times that of the BW-ARNCO-100XT^TM weld layer, and the wear resistance of the SFSR-Ni60 weld layer is 2.45 times that of the BW-ARNCO-100XT^TM weld layer. The anti-friction properties of SFSR-Ni60 welding layer is the best, followed by HVOF-Cr₃C₂75-NiCr25 coating, and the anti-friction properties of BW-ARNCO-100XT^TM welding layer is the worst among the three.

The research results of this paper have great practical value in the process and material of improving the wear resistance and anti-friction performance of the drill pipe joint casing.