Chenjie Wang, Lu Yin, Qing Zhao, Wei Wang, Chengyuan Li and Bin Luo
To ensure the safety of electric power supply, it is necessary to inspect substation equipment. With the dramatic increase in the number of substations, especially indoor…
Abstract
Purpose
To ensure the safety of electric power supply, it is necessary to inspect substation equipment. With the dramatic increase in the number of substations, especially indoor substations, intelligent robot inspection has become an important development direction. This paper aims to describe the design of a trackless robot with a robotic arm, which is capable of navigating autonomously and inspecting the equipment in a narrow and complex indoor substation.
Design/methodology/approach
A robust four-wheel platform powered by electric motors is used to carry the robot. By fusing multiple-sensor data and visual markers, the robot achieves autonomous movement based on simultaneous localization and mapping. In addition, to accurately obtain the reading of meters located at height or in a narrow space, the robot is equipped with a newly designed visual servo robotic arm.
Findings
In practical application, the robot satisfies the requirements of substation inspection, improves work efficiency, saves costs and achieves good results. The robot is also approved by the relevant departments of the State Grid Corporation of China.
Practical implications
After stable operation in a substation for a period of one year, the robot shows high efficiency and stability, meeting the requirements of indoor substation inspection. Meanwhile, the robot greatly promoted the realization of indoor and outdoor integrated substation automatic inspection, and is expected to be further applied in other industrial inspection sites, including mine, tunnel and nuclear power plant.
Originality/value
Due to the complex indoor environment, most of the existing inspection robots are only used outdoors, and there are no good trackless inspection robots for use indoors. The proposed robot is a trackless intelligent inspection robot for use in indoor substations. The robot features a number of important modules, including an autonomous localization and navigation module and a visual servo manipulator module, which can be used in narrow spaces or at height.
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Chunyu Yang and Jue Huang
Spatial integration and industrial clustering have become an important feature of the culture tourism business. When the core elements in both the culture industry and tourism…
Abstract
Spatial integration and industrial clustering have become an important feature of the culture tourism business. When the core elements in both the culture industry and tourism industry are integrated, a model based on system science is constructed that combines the resources and capacity of the two entities to envisage the ways of creating integrated products and services from the two sectors. Guided by the system science, this study proposes a culture tourism system revealing the clustering and hierarchical structure of the industrial elements. The system contains two subsystems: internal system and external system. The agglomeration model of the system includes 26 indices and the PEF methods, which involved the Parallelogram Law, Entropy-weight Method, and Fuzzy Membership Function. Finally, this study deploys an empirical study involving all provincial territories (N=31) in mainland China. It analyzes the variability and degree of balanced development of the system. In addition, through the resultant data this research adds a typology of culture tourism system along with policy recommendations.
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Yongtao Yao, Yuncheng Xu, Bing Wang, Weilong Yin and Haibao Lu
The purpose of this paper is to provide a review of recent systematic and comprehensive advancement in electrospun polymer fiber and their composites with shape memory property.
Abstract
Purpose
The purpose of this paper is to provide a review of recent systematic and comprehensive advancement in electrospun polymer fiber and their composites with shape memory property.
Design/methodology/approach
The nanofiber manufacture technique is initially reviewed. Then, the influence of electrospinning parameters and actuation method has been discussed. Finally, the study concludes with a brief review of recent development in potential applications.
Findings
Shape memory polymer (SMP) nanofibers are a type of smart materials which can change shape under external stimuli (e.g. temperature, electricity, magnetism, solvent). In general, such SMP nanofibers could be easily fabricated by mature electrospinning technique. The nanofiber morphology is mainly affected by the electrospinning parameters, including applied voltage, tip-to-collector distance, viscosity of solution, humidity and molecular weight. For actuation method, most SMP nanofibers and their composites can change their shapes in response to heat, magnetic field or solvent, while few can be driven by electricity. Compared with the block SMPs, electrospun SMP nanofibers’ mat with porosity and low mechanical property have a wide potential application field including tissue engineering, drug delivery, filtration, catalysis.
Originality/value
This paper provides a detailed review of shape memory nanofibers: fabrication, actuation and potential application, in the near future.
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Dilong Chen, Qiang Lu, Dongliang Peng, Ke Yin, Chaoliang Zhong and Ting Shi
The purpose of this paper is to propose a receding horizon control approach for the problem of locating unknown wireless sensor networks by using a mobile robot.
Abstract
Purpose
The purpose of this paper is to propose a receding horizon control approach for the problem of locating unknown wireless sensor networks by using a mobile robot.
Design/methodology/approach
A control framework is used and consists of two levels: one is a decision level, while the other is a control level. In the decision level, a spatiotemporal probability occupancy grid method is used to give the possible positions of all nodes in sensor networks, where the posterior probability distributions of sensor nodes are estimated by capturing the transient signals. In the control level, a virtual robot is designed to move along the edge of obstacles such that the problem of obstacle avoidance can be transformed into a coordination problem of multiple robots. On the basis of the possible positions of sensor nodes and virtual robots, a receding horizon control approach is proposed to control mobile robots to locate sensor nodes, where a temporary target position method is utilized to avoid several special obstacles.
Findings
When the number of obstacles increases, the average localization errors between the actual locations and the estimated locations significantly increase.
Originality/value
The proposed control approach can guide the mobile robot to avoid obstacles and deal with the corresponding dynamical events so as to locate all sensor nodes for an unknown wireless network.
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Meiqun Yin and Lei Sheng
This paper aims to find the endogenous relationship between innovation input and corporate performance and deepen the study of innovation performance theory in industry and…
Abstract
Purpose
This paper aims to find the endogenous relationship between innovation input and corporate performance and deepen the study of innovation performance theory in industry and enterprise at the micro level.
Design/methodology/approach
This paper selects the firms listed on A shares in Shanghai and Shenzhen Stock Exchanges from 2009 to 2015 as samples. The authors cluster these samples according to the factors of production and classify the samples into three types: technology-intensive, capital-intensive and labor-intensive. After obtaining the samples and classifying them, the authors conduct a research on the endogenous relationship between the innovation input and the corporate performance through the simultaneous equations model and 3SLS estimation method. Meanwhile, they also make a study on the influence of executive incentive mechanism on the relationship between the innovation input and the corporate performance.
Findings
In technology-intensive industry, the increase of pre-innovation input will enhance the corporate performance in the current period, however, which will slow down the pace of innovation and lead to lower corporate performance in the future, and then increase innovation input again. In contrast, in capital-intensive industries, innovation input just improves corporate performance in the current period and the promotion of corporate performance will promote the intensity of innovation input in the future. With labor-intensive industries, innovation input also depends on early good returns, but innovation input has no significant impact on the corporate performance both at present and in the future. While in the executive incentive mechanism, salary incentive has a significant positive regulatory effect on the relationship between innovation input and corporate performance.
Originality/value
This paper presents a new research perspective on the relationship between innovation input and firm corporate performance, which is of great value to the listed company in balancing the R&D input with the company’s target performance and the design of executive incentive mechanism.
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Valeria Gattai and Piergiovanna Natale
In this chapter, we document the growing importance of FDI from BRIC countries in relation to FDI from both developed and developing countries and investigate the types of firms…
Abstract
Purpose
In this chapter, we document the growing importance of FDI from BRIC countries in relation to FDI from both developed and developing countries and investigate the types of firms that are responsible for BRIC FDI.
Methodology/approach
We follow a two-step empirical approach. First, we provide macro evidence on FDI from BRIC countries. We use UNCTAD data to highlight the patterns of FDI flows and stocks. Second, we provide firm-level evidence on FDI. Using ORBIS data, we elaborate a rich taxonomy of FDI that accounts for the decision to invest abroad and for the location, ownership, and number of foreign subsidiaries. Thus, we characterize BRIC multinationals’ involvement in FDI and examine the relationship between FDI and performance at the firm level.
Findings
We unveil new facts about BRIC multinationals. BRIC multinationals are in the minority in their home countries, but they outperform domestic enterprises. Within the group of BRIC investors, those firms that invest in developing countries, that operate in joint ventures, or that have more than five foreign subsidiaries are in the minority, but they outperform those firms that select other FDI strategies.
Research limitations/implications
Our estimates document a positive and robust correlation between FDI and performance; however, the cross-sectional nature of our data does not permit a proper causality analysis.
Originality/value
Our work contributes to the International Economics literature on internationalization and firm performance as well as to the International Business literature on FDI from emerging economies. With respect to the former, we innovate by studying the relation between FDI strategies and firm performance. In relation to the latter, we innovate by introducing firm-level data and a cross-country approach that lets us illustrate the roles and features of FDI from BRIC countries.
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In these times of globalisation, distances are getting smaller, enhancing the interactions between people of different cultural backgrounds. This is especially true in the area of…
Abstract
In these times of globalisation, distances are getting smaller, enhancing the interactions between people of different cultural backgrounds. This is especially true in the area of tourism, a field that is shaped by manifold communication activities. The enormous increases in the numbers of Chinese tourists visiting Europe and other Western destinations require building up intercultural competencies to minimise conflicts and promote mutual understanding. It is therefore necessary to question one’s own cultural view, which is why the debate surrounding de-Westernisation is of crucial importance. The metaphor of the atmosphere – in Chinese qifen – offers a helpful access point to strengthen mutual understanding, because it creates a bridge between eastern and western thinking. Paul Watzlawick (1967) developed his well-known five axioms of communication, the second of which states that every communication has both content and a relational aspect, and the latter classifies the former. This chapter shows why the atmospheric dimension of communication should be established as the third axiom in order to understand communication holistically.
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Abstract
Purpose
This paper discusses the use of modelling techniques to predict the reliability of an anisotropic conductive film (ACF) flip chip in a humid environment. The purpose of this modelling work is to understand the role that moisture plays in the failure of ACF flip chips.
Design/methodology/approach
A 3D macro‐micro finite element modelling technique was used to determine the moisture diffusion and moisture‐induced stresses inside the ACF flip chip.
Findings
The results show that the ACF layer in the flip chip can be expected to be fully saturated with moisture after 3 h at 121°C, 100%RH, 2 atm test conditions. The swelling effect of the adhesive due to this moisture absorption causes predominately tensile stress at the interface between the adhesive and the metallization, which could cause a decrease in the contact area, and therefore an increase in the contact resistance.
Originality/value
This paper introduces a macro‐micro modelling technique which enables more detailed 3D modelling analysis of an ACF flip chip than previously.
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Yan Yin, Xingming Xiao, Jiusheng Bao, Jinge Liu, Yuhao Lu and Yangyang Ji
The purpose of this study is to establish a new temperature set for characterizing the frictional temperature rise (FTR) of disc brakes. The FTR produced by braking is an…
Abstract
Purpose
The purpose of this study is to establish a new temperature set for characterizing the frictional temperature rise (FTR) of disc brakes. The FTR produced by braking is an important factor which directly affects the tribological properties of disc brakes. Presently, most existing researches characterize the FTR only by several static parameters such as average temperature or maximum temperature, which cannot reflect accurately the dynamic characteristics of temperature variation in the process of braking. In this paper, a new temperature parameter set was extracted and the influences of braking conditions on these parameters were investigated by experiments.
Design/methodology/approach
First, several simulated braking experiments of disc brakes were conducted to reveal the dynamic variation rules and mechanisms of the FTR in braking. Second, the characteristic parameter subset of the FTR was extracted with five significant parameters, namely, initial temperature, average temperature, end temperature, maximum temperature and the ratio of maximum temperature time. Furthermore, the fitting parameter subset of the FTR was constructed based on the temperature rise curve. Finally, the influence and mechanisms of initial braking velocity and braking pressure on the new temperature parameter set were investigated through braking experiments.
Findings
This paper extracted a new temperature parameter set including a characteristic parameter subset and a fitting parameter subset and revealed the influences of braking conditions on it by experiments.
Originality/value
The results showed that the new temperature parameter set extracted in this paper can characterize the dynamic characteristics of disc brake’s FTR variations more objectively and comprehensively. The research results will provide a theoretical basis for extracting the fault feature of friction properties.
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Wu Qin, Hui Yin, D.J. Yu and Wen-Bin Shangguan
This paper aims to develop an efficient numerical method for mid-frequency analysis of built-up structures with large convex uncertainties.
Abstract
Purpose
This paper aims to develop an efficient numerical method for mid-frequency analysis of built-up structures with large convex uncertainties.
Design/methodology/approach
Based on the Chebyshev polynomial approximation technique, a Chebyshev convex method (CCM) combined with the hybrid finite element/statistical energy analysis (FE-SEA) framework is proposed to fulfil the purpose. In CCM, the Chebyshev polynomials for approximating the response functions of built-up structures are constructed over the uncertain domain by using the marginal intervals of convex parameters; the bounds of the response functions are calculated by applying the convex Monte–Carlo simulation to the approximate functions. A relative improvement method is introduced to evaluate the truncated order of CCM.
Findings
CCM has an advantage in accuracy over CPM when the considered order is the same. Furthermore, it is readily to consider the CCM with the higher order terms of the Chebyshev polynomials for handling the larger convex parametric uncertainty, and the truncated order can be effectively evaluated by the relative improvement method.
Originality/value
The proposed CCM combined with FE-SEA is the first endeavor to efficiently handling large convex uncertainty in mid-frequency vibro-acoustic analysis of built-up structures. It also has the potential to serve as a powerful tool for other kinds of system analysis when large convex uncertainty is involved.