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The purpose of this study is to present the state of the art for fiber Bragg grating (FBG) acceleration sensing technologies from two aspects: the principle of the measurement dimension and the principle of the sensing configuration. Some commercial sensors have also been introduced and future work in this field has also been discussed. This paper could provide an important reference for the research community.

This review is to present the state of the art for FBG acceleration sensing technologies from two aspects: the principle of the measurement dimension (one-dimension and multi-dimension) and the principle of the sensing configuration (beam type, radial vibration type, axial vibration type and other composite structures).

The current research on developing FBG acceleration sensors is mainly focused on the sensing method, the construction and design of the elastic structure and the design of a new information detection method. This paper hypothesizes that in the future, the following research trends will be strengthened: common single-mode fiber grating of the low cost and high utilization rate; high sensitivity and strength special fiber grating; multi-core fiber grating for measuring single-parameter multi-dimensional information or multi-parameter information; demodulating equipment of low cost, small volume and high sampling frequency.

The principle of the measurement dimension and principle of the sensing configuration for FBG acceleration sensors have been introduced, which could provide an important reference for the research community.

A pine/co-PES composite (PCPES composite) was proposed as the feedstock for powder bed fusion (laser sintering, LS). This paper aims to provide some necessary experimental data and the theoretical foundation for LS of pine/co-PES, especially for the application of using the laser-sintered pine/co-PES parts as complex structural patterns in investment casting.

The PCPES composites with different pine loadings were mixed mechanically. The composite’s preheating temperature and processing temperature during LS were determined experimentally based on the material’s thermal behavior. The effects of pine powder on the binding mechanism of PCPES composites were discussed through analyzing the microstructure of the laser-sintered parts’. Mechanical properties and dimensional precision of laser-sintered PCPES parts in different pine loadings were tested, and the parts’ mechanical properties were strengthened by wax-infiltration post-processing. The influence extents of process parameters on the mechanical properties of laser-sintered 20 Wt.% pine/co-PES parts were investigated using a 1/2 fractional factorials experiment.

20 Wt.% pine/co-PES is considered to be a promising wood-plastic composite for laser sintering. The relationship between mechanical strength of its laser-sintered parts and process parameters was built up using mathematical formulas. Experimental results show density, tensile strength, flexural strength and surface roughness of laser-sintered 20 Wt.% pine/co-PES parts are improved by 72.7-75.0%, 21.9-111.3%, 26.8-86.2%, 27.0-29.1% after post-process infiltration with a wax. A promising application of the wax-infiltrated laser-sintered parts is for investment casting cores and patterns.

The proper process parameters and forming properties of laser-sintered parts are limited to the results of laser sintering experiments carried on using AFS 360 rapid prototyping device.

This investigation not only provides a new feedstock for laser sintering with the advantages of low cost and fabricability but also uses an advanced technique to produce personalized wood-plastic parts efficiently. Mathematical models between mechanical properties of laser-sintered PCPES parts and LS process parameters will guide the further LS experiments using the 20 Wt.% pine/co-PES composite. Besides, the laser-sintered PCPES parts after wax-infiltration post-processing are promising as complex structural patterns for use in investment casting.

A new kind of polymer mixture (co-PA-PES) was prepared in different mass ratios, by mixing polyether sulfone hot-melt adhesive (PES-HmA) and copolyamide B249 (PA-B249). This study aims to investigate its characteristics of laser sintering and get the optimal process parameters.

The effect of mass ratio of co-PA-PES on thermal behavior was analyzed using a simultaneous thermal analyzer, and the density and mechanical properties of sintered parts were tested to evaluate the performance of the polymeric system. Scanning electron microscopy and Fourier transform infrared spectroscopy were performed to characterize the microstructure and binding mechanism of sintered co-PA-PES parts. Specifically, mechanical properties of the mixture with 20 Wt.% PA-B249 were optimized based on a design of experiment methodology, along with the restriction of maximum absorbable laser energy density.

Liquid phase fusion was considered as the main sintering mechanism for co-PA-PES, and mechanical interlocking was the dominant binding mechanism. The effects of mass ratios of this material on the thermal properties, density and mechanical properties were obtained via data results. Additionally, compared to neat PES-HmA, co-20 Wt.% PA-PES showed a 71.7 per cent increase in tensile strength, 24.4 per cent increase in flexural strength and 102.1per cent increase in impact strength.

This paper proposed a new kind of polymer mixture as the feedstock for laser sintering with the advantages of low price and easy processing. The filler of PA-B249 effectively improved the performance of the polymer mixture, including but not limited to mechanical properties.

In recent decades many emerging markets (EMFs) have undertaken entrepreneurial transformations to adapt to institutional transition and industrial change. Corporate entrepreneurship (CE) provided EMFs viable ways to revitalize, reconfigure, and transform successfully with the dynamic environment. Although previous research examined government roles on EMFs' CE activities, little is known about the mechanisms of how government exerts influence on CE activities. To fully understand CE of EMFs, we propose a stage model to explore specific roles governments play that affect CE activities over time. In particular, we investigate how governments' grabbing hand, helping hand, and invisible hand roles affected Chinese auto firms' CE activities at different stages from 1980 to 2016. Government involvement is summarized and the advantages and disadvantages of these roles are analyzed.

The aero-engine array electrostatic monitoring technology (AEMT) can provide more and more accurate information about the direct product of the fault, and it is a novel condition monitoring technology that is expected to solve the problem of high false alarm rate of traditional electrostatic monitoring technology. However, aliasing of the array electrostatic signals often occurs, which will greatly affect the accuracy of the information identified by using the electrostatic sensor array. The purpose of this paper is to propose special solutions to the above problems.

In this paper, a method for de-aliasing of array electrostatic signals based on compressive sensing principle is proposed by taking advantage of the sparsity of the distribution of multiple pulse signals that originally constitute aliased signals in the time domain.

The proposed method is verified by finite element simulation experiments. The simulation experiments show that the proposed method can recover the original pulse signal with an accuracy of 96.0%; when the number of pulse signals does not exceed 5, the proposed method can recover the pulse peak with an average absolute error of less than 5.5%; and the recovered aliased signal time-domain waveform is very similar to the original aliased signal time-domain waveform, indicating that the proposed method is accurate.

The proposed method is one of the key technologies of AEMT.

This study aims to explore the relationship between corporate environmental information disclosure and digital finance.

The authors used Chinese listed enterprises as the sample. Data on digital finance are from the China Digital Inclusive Finance Index published by the Institute of Digital Finance of Peking University, and corporate environmental information disclosure is collected from the China Securities Market and Accounting Research database. Multivariate regression and Stata software were used for data analysis.

The findings suggest that digital finance significantly inhibits firms’ environmental information disclosure. Digital finance increases firms’ motivation to meet low-income customers’ demands, which is achieved at the expense of environmental performance, leading to deteriorated environmental information disclosure. Furthermore, this inhibitory effect is exacerbated by managerial power but mitigated by institutional shareholdings and political connections.

The findings have important implications for policymakers and managers when formulating relevant policies regarding the co-development of digital finance and corporate environmental information disclosure.

Environmental information disclosure is a crucial element in CSR disclosure quality.

This study enriches the literature on the environmental influences of digital finance by examining the relationship between digital finance and corporate environmental information disclosure, a crucial way through which external stakeholders obtain information about corporate environmental behaviours.

The formation and corrosion processes of a conversion film on the AZ80 Mg alloy with different second phases were compared to clarify the effect of microstructure on the quality of protective coatings.

The size and distribution of second phases in the edge and central regions of the AZ80 cast ingot exhibit a great difference. The film growth processes and their corrosion resistance on the edge and central regions of the AZ80 cast ingot were investigated by scanning electron microscope observations, immersion tests and electrochemical measurements.

The results indicate that second phases act as micro-cathodes and hydrogen evolution reaction occurs on their surface, which is not beneficial for the deposition of the conversion film.

The conversion film formed on the central regions of AZ80 cast ingot with a low volume fraction of second phases exhibits a more uniform surface and higher corrosion resistance than that formed on the edge regions of the sample with a higher volume fraction of second phases.

The purpose of the study was to explore the intention of micro and small enterprises’ (MSEs) owners to adopt digital technologies as a strategy to catalyze sustainable growth of Uganda's economy.

This study adopted a qualitative, multi-case design. The unit of inquiry consisted of business owners operating in St. Balikuddembe Market, Kampala, Uganda. They were interrogated to explore their intention to adopt digital technologies during the total lockdown as a strategy to sustainably operate their businesses.

A total of four major themes emerged from the data analysis process and these are the impact of coronavirus disease 2019 (COVID-19) on business operations, awareness of digital technologies, usage of digital technologies and intention to use more digital technologies.

The findings of the study shed light on what policymakers, digital service providers and business owners can do to improve uptake of digital technologies among MSEs in Uganda.

This study contributes to the extant literature on digital technologies in MSEs using evidence from Uganda's informal sector. The results of the study may catalyze uptake of digital technologies as policymakers and digital service providers will devise appropriate strategies that will enable business owners to integrate these technologies into their business operations.