Search results

The purpose of this paper is to design a current transformer model based on the principle of B-dot. It can reflect the change of transmission line current and meet the requirement of automation and intelligence for current measurement in power system.

In this paper, a new type of current transformer is designed on the principle of B-dot, which has the structure of the inverse series of planar air core coils and the form of printed circuit board (PCB). With this structure, the current transformers can induce magnetic field quite well. The finite element simulation for the current transformer with n layers structure is conducted in the Maxwell, which help to optimize the design of the current transformer.

By setting up the experimental platform, the experiment of the current transformer is carried out. The results of the test show that the measurement accuracy can satisfy the requirement of measurement. Besides, the new current transformer has good transient characteristics and can meet the needs of the development of smart grid.

The new type of current transformer is based on the principle of B-dot, which is designed with a new type of non-contact PCB hollow coil current transformer. It has no iron core, no ferromagnetic effect and the phenomenon of ferromagnetic resonance. It has great progress in its insulation performance, volume and bandwidth response. In addition, the planar hollow coil of the inverse series structure can make the structure more accurate.

A new wire arc additive manufacturing (WAAM) process combined with gravity-driven powder feeding was developed to fabricate components of tungsten carbide (WC)-reinforced iron matrix composites. The purpose of this study was to investigate the particle transportation mechanism during deposition and determine the effects of WC particle size on the microstructure and properties of the so-fabricated component.

Thin-walled samples were deposited by the new WAAM using two WC particles of different sizes. A series of in-depth investigations were conducted to reveal the differences in the macro morphology, microstructure, tensile performance and wear properties.

The results showed that inward convection and gravity were the main factors affecting WC transportation in the molten pool. Large WC particles have higher ability than small particles to penetrate into the molten pool and survive severe dissolution. Small WC particles were more likely to be completely dissolved around the top surface, forming a thicker region of reticulate (Fe, W)₆C. Large WC particles can slow down the inward convection more, thereby leading to an increase in width and a decrease in the layer height of the weld bead. The mechanical properties and wear resistance significantly increased owing to reinforcement. Comparatively, samples with large WC particles showed inferior tensile properties owing to their higher susceptibility to cracks.

Fabricating metal matrix composites through the WAAM process is a novel concept that still requires further investigation. Apart from the self-designed gravity-driven powder feeding, the unique aspects of this study also include the revelation of the particle transportation mechanism of WC particles during deposition.

China's digital economy is flourishing and playing a pivotal role in the national economy. Government subsidies, as an important tool for the national treasury, are a “reassurance” for the digital transformation of manufacturing enterprises. The purpose of this paper is to investigate the relations between the digital transformation of manufacturing enterprises and government subsidies to provide inspiration for promoting the digitization and upgrading of China's manufacturing industry and facilitate enterprises' innovative development.

Based on the panel data of 2,928 manufacturing listed companies in China from 2016 to 2020, this paper empirically tests the effect of subsidies on the digital transformation of manufacturing enterprises using fixed-effect econometric regression.

The results illustrate that subsidies effectively incentivize digital transformation in manufacturing enterprises, and verify different situations through heterogeneity. Further analysis of the moderating effect shows that the innovation level and servitization level of manufacturing enterprises positively moderated the relationship between government subsidies and the enterprise's digital transformation.

Based on Chinese manufacturing enterprise samples, this paper empirically tests the incentive effect of government subsidies on the digital transformation of manufacturing enterprises, therefore clarifying the main regulatory effects. This paper could provide enlightenment for manufacturing enterprises to make good use of government subsidies to improve their digital ability, thereby enhancing competitiveness in the digital economy era.

The purpose of this paper is to investigate the relations between the digital transformation of manufacturing enterprises and enterprise innovation to provide inspiration for promoting the digitization and upgrading of China's manufacturing industry and facilitate enterprises' innovative development.

Based on a panel data of 584 listed manufacturing companies in China from 2016 to 2020, and using a fixed effects approach, this paper empirically examines the impact of digital transformation on corporate innovation in manufacturing enterprises, as well as examining the influential mechanisms and heterogeneity.

The research shows that the digital transformation of manufacturing enterprises has effectively improved the innovation capacity of enterprises and verifies different situations through heterogeneity. At the same time, the research clarifies the mediating effect of the innovation investment mechanism, cost control mechanism, and profit guarantee mechanism on the relations between the digital transformation of manufacturing enterprises and the innovation capacity of enterprises.

Based on Chinese manufacturing enterprise samples, this paper empirically tests the influential mechanism of digital transformation on the innovation capability of manufacturing enterprises, therefore clarifying the main mediating effects. This paper could provide inspiration for manufacturing companies to make good use of digital transformation rules according to their own situation and improve their innovation capabilities, thereby enhancing competitiveness in the digital economy era.

The rising volume of open government data (OGD) contrasts with the limited acceptance and utilization of OGD among citizens. This study investigates the reasons for citizens’ not using available OGD by comparing citizens’ attitudes towards OGD with the development of OGD portals. The comparison includes four OGD utilization processes derived from the literature, namely OGD awareness, needs, access and consumption.

A case study in China has been carried out. A sociological questionnaire was designed to collect data from Chinese citizens (demand), and personal visits were carried out to collect data from OGD portals (supply).

Results show that Chinese citizens have low awareness of OGD and OGD portals. Significant differences were recognized between citizens’ expectations and OGD portals development in OGD categories and features, data access services and support functions. Correlations were found between citizens’ OGD awareness, needs, access and consumption.

By linking the supply of OGD from the governments with each process of citizens’ OGD utilization, this paper proposes a framework for citizens’ OGD utilization lifecycle and provides a new tool to investigate reasons for citizens’ not making use of OGD.