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1 – 10 of 97Feng Wang, Zhiqiang Wu, Yajie Li and Yuancen Wang
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…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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.
Originality/value
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.
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Chuanfu Chen, Zhiqiang Wu, Dan Wu and Congjing Ran
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.
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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.
Originality/value
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.
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Chuanfu Chen, Zhiqiang Wu, Congjing Ran, Qiong Tang, Song Chen and Xiaojuan Zhang
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…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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.
Originality/value
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.
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Edna Pasher, Otthein Herzog, Mor Harir, Yaara Turjeman-Levi and Wu Zhiqiang
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…
Abstract
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.
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Zhenyang Zhu, Yi Liu, Zhe Fan, Sheng Qiang, Zhiqiang Xie, Weimin Chen and Congcong Wu
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…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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.
Originality/value
This new method can improve the calculation accuracy of the embedded element method and make the calculation results more reasonable and reliable.
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Hongyu Li, Junjie Wu and Zhiqiang Lu
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…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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.
Originality/value
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.
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Zhiqiang Zhou, Yong Fu and Wei Wu
The human-following task is a fundamental function in human–robot collaboration. It requires a robot to recognize and locate a target person, plan a path and avoid obstacles. To…
Abstract
Purpose
The human-following task is a fundamental function in human–robot collaboration. It requires a robot to recognize and locate a target person, plan a path and avoid obstacles. To enhance the applicability of the human-following task in various scenarios, it should not rely on a prior map. This paper aims to introduce a human-following method that meets these requirements.
Design/methodology/approach
For the identification and localization of the target person (ILTP), this paper proposes an approach that integrates data from a camera, a light detection and ranging (LiDAR) and a ultra-wideband (UWB) anchor. For path planning and obstacle avoidance, a modified timed-elastic-bands (TEB) algorithm is introduced.
Findings
Compared to the UWB-only method, where only UWB is used to locate the target person, the proposed ILTP method in this paper reduces the localization error by 41.82%. Experimental results demonstrate the effectiveness of the ILTP and the modified TEB method under various challenging conditions. Such as crowded environments, multiple obstacles, the target person being occluded and the target person moving out of the robot’s field of view. The complete experimental videos are available for viewing on https://youtu.be/ZKbrNE1sePM.
Originality/value
This paper offers a novel solution for human-following tasks. The proposed ILTP method can recognize the target person among multiple individuals, determine whether the target person is lost and publish the target person’s position at a frequency of 20 Hz. The modified TEB algorithm does not rely on a prior map. It can plan paths and avoid obstacles effectively.
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Zhiqiang Lu, Junjie Wu and Jia Liu
The promotion of financial inclusion can disturb the composition of traditional bank concentration and change the relationship between bank concentration and the availability of…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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.
Originality/value
This study provides new insights into the relationship between bank concentration and SME finance availability under the promotion of financial inclusion.
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Duzhou Zhang, Zhiguo Tian, Zhiqiang Chen, Dengyun Wu, Gang Zhou, Shaohua Zhang and Moran Wang
The purpose of this paper is to investigate the evolution of the permeability of spherical packing during cold compaction by pore-scale modeling.
Abstract
Purpose
The purpose of this paper is to investigate the evolution of the permeability of spherical packing during cold compaction by pore-scale modeling.
Design/methodology/approach
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.
Findings
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.
Research limitations/implications
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.
Originality/value
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.
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