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This paper aims to develope the electromagnetic interference shielding materials with high performance. To develop advanced polymer-based electromagnetic interference shielding materials with rather high temperature stability, good processability and moderate mechanical properties, the authors chose the polyimide (PI) foam as matrix and ferriferrous oxide (Fe₃O₄) as fillers to prepare the composite foams with lightweight and rather good electromagnetic interference shielding performance.

Some polyimide nanocomposite foams with Fe₃O₄ as fillers have been prepared by in situ dispersion and foaming with pyromellitic dianhydride (PMDA) and isocyanate (PAPI) as raw materials and water as foaming agent. By varying the Fe₃O₄ contents, a series of PI/Fe₃O₄ nanocomposite foams with fine microstructures and high thermal stability were obtained. The structure and performances of nanocomposite foams were examined, and the effects of Fe₃O₄ on the microstructure and properties of composite foams were investigated.

This work demonstrates that PI/Fe₃O₄ foams could be fabricated by thermally treating the polyimide foam intermediates with Fe₃O₄ nanoparticles through a blending reaction of precursors. The final PI/Fe₃O₄ composite foams maintained the excellent thermal property and showed a super paramagnetic behaviour, which has a positive effect on the improvement of electromagnetic shielding performance.

In this paper, the effects of Fe₃O₄ on the performances of PI/Fe₃O₄ composite foam were reported. It provided an effective methodology for the preparation of polymer/Fe₃O₄ nanocomposite foams, which hold great promise towards the potential application in the areas of electromagnetic shielding materials.

A series of PI/Fe₃O₄ composite foams with different contents of Fe₃O₄ were prepared by blending reaction of the precursors. The effects of Fe₃O₄ on the structures and properties of PI/Fe₃O₄ composite foam were discussed in detail.

Polylactide/nano‐silica in situ composites are synthesised and characterised in order to study their mechanical and thermal properties. The purpose of this paper is to study these properties and compare them with the pure polylactide (PLA).

Polylactide/nano‐silica in situ composites are synthesised from lactide and modified nano‐silica using stannous octoate as a catalyst. The structure and properties of the composites are characterised by gel permeation chromatography (GPC), thermal gravimetric analysis (TGA) and scanning electronic microscopy (SEM).

The results of SEM showed that nano‐silica and PLA are connected with covalent bonds, and that inorganic phases are dispersed homogeneously in the PLA matrix. The results of TGA indicated that the thermal decomposition temperature rose with the increase of silica content. The tensile strength of the composites is enhanced because of the addition of nano‐inorganic particles into PLA.

Although the preparation process is simplified by a two‐step method, attempts will be made to synthesise the polylactide/nano‐silica composites by a one‐step approach to curtail the preparation cycle.

The composites are expected to be suitable for applications in packaging materials, biomedical and pharmaceutical fields.

Preparation of polylactide/nano‐silica composites is expected to exert the respective advantages of the two ingredients and to produce more practical polymer materials.

Drawing from social capital theory and resource dependence theory, this paper aims to test the relationship between top management team (TMT) government social capital and firm’s innovation performance via firm’s network prestige, and the moderating effect of TMT academic social capital.

The authors collected data from the China Stock Market and Accounting Research Database as well as A-share listed firms’ annual reports, and finally generated a sample of 922 firms and 2,464 firm-years from 2008 to 2014. UCINET 6.0 was used to analyze the data.

The authors find that the government social capital of TMT is positively related to firms’ innovation performance and firms’ network prestige plays a mediating role in this relationship. In addition, TMT academic social capital can strengthen the links between TMT government social capital and innovation performance through firms’ network prestige.

This paper not only contributes to literatures on the mechanism in the relationship between government social capital and firms’ innovation, but also to literatures on the effectiveness of the heterogeneity of firm’s social capital.

The type 120 emergency valve is an essential braking component of railway freight trains, but corresponding diaphragms consisting of natural rubber (NR) and chloroprene rubber (CR) exhibit insufficient aging resistance and low-temperature resistance, respectively. In order to develop type 120 emergency valve rubber diaphragms with long-life and high-performance, low-temperatureresistant CR and NR were processed.

The physical properties of the low-temperature-resistant CR and NR were tested by low-temperature stretching, dynamic mechanical analysis, differential scanning calorimetry and thermogravimetric analysis. Single-valve and single-vehicle tests of type 120 emergency valves were carried out for emergency diaphragms consisting of NR and CR.

The low-temperature-resistant CR and NR exhibited excellent physical properties. The elasticity and low-temperature resistance of NR were superior to those of CR, whereas the mechanical properties of the two rubbers were similar in the temperature range of 0 °C–150 °C. The NR and CR emergency diaphragms met the requirements of the single-valve test. In the low-temperature single-vehicle test, only the low-temperature sensitivity test of the NR emergency diaphragm met the requirements.

The innovation of this study is that it provides valuable data and experience for future development of type 120 valve rubber diaphragms.

This paper reviews the literature on zombie firms to provide a holistic view by delineating their formation, impact, widespread nature, prevention and policy implications.

This paper uses a systematic literature review methodology, in which 76 papers published in journals ranked on the Australian Business Deans Council (ABDC) 2022 list were reviewed. The study period was from 2000 to 2022.

Among the main findings, the widespread problems of zombie firms were evident. The authors found that consistent support, either in the form of government grants or a weak financial framework, was responsible for their formation. The suboptimal performance of factors of production, depressed job creation, low innovation and overall negative impact on economic activity are the consequences of zombification. This can be controlled by ensuring better bankruptcy codes, focused on government assistance, technology use and better due diligence by banks.

This review serves as a reference point for future researchers as a cohesive and holistic study presenting a full picture of the problem, so that the proposed solutions are robust and tenable.

This review is among the initial attempts to comprehensively study published work on zombie firms in terms of analyzing their region-specific nature, with an emphasis on definition, causes, impact and prevention.

With the yearly increase of mileage and passenger volume in China's high-speed railway, the problems of traditional paper railway tickets have become increasingly prominent, including complexity of business handling process, low efficiency of ticket inspection and high cost of usage and management. This paper aims to make extensive references to successful experiences of electronic ticket applications both domestically and internationally. The research on key technologies and system implementation of railway electronic ticket with Chinese characteristics has been carried out.

Research in key technologies is conducted including synchronization technique in distributed heterogeneous database system, the grid-oriented passenger service record (PSR) data storage model, efficient access to massive PSR data under high concurrency condition, the linkage between face recognition service platforms and various terminals in large scenarios, and two-factor authentication of the e-ticket identification code based on the key and the user identity information. Focusing on the key technologies and architecture the of existing ticketing system, multiple service resources are expanded and developed such as electronic ticket clusters, PSR clusters, face recognition clusters and electronic ticket identification code clusters.

The proportion of paper ticket printed has dropped to 20%, saving more than 2 billion tickets annually since the launch of the application of E-ticketing nationwide. The average time for passengers to pass through the automatic ticket gates has decreased from 3 seconds to 1.3 seconds, significantly improving the efficiency of passenger transport organization. Meanwhile, problems of paper ticket counterfeiting, reselling and loss have been generally eliminated.

E-ticketing has laid a technical foundation for the further development of railway passenger transport services in the direction of digitalization and intelligence.

This paper aims to analyze how decision support systems manage Big data to obtain value.

A systematic literature review was performed with screening and analysis of 72 articles published between 2012 and 2019.

The findings reveal that techniques of big data analytics, machine learning algorithms and technologies predominantly related to computer science and cloud computing are used on decision support systems. Another finding was that the main areas that these techniques and technologies are been applied are logistic, traffic, health, business and market. This article also allows authors to understand the relationship in which descriptive, predictive and prescriptive analyses are used according to an inverse relationship of complexity in data analysis and the need for human decision-making.

As it is an emerging theme, this study seeks to present an overview of the techniques and technologies that are being discussed in the literature to solve problems in their respective areas, as a form of theoretical contribution. The authors also understand that there is a practical contribution to the maturity of the discussion and with reflections even presented as suggestions for future research, such as the ethical discussion. This study’s descriptive classification can also serve as a guide for new researchers who seek to understand the research involving decision support systems and big data to gain value in our society.

Social question and answer (SQA) site is one of the factors that boosted up and popularized the vision of social web. It enables community members to post highly valued answers to globally asked questions and information seekers to grab intellectual information in a contextual, concise, and meaningful format at the cost of investing a few minutes. The purpose of this paper is to present a common architecture, history, and a comprehensive review of such sites.

A critical and analytical investigation of the state-of-the-art SQA sites and relevant literature has been carried out with the intention to explore the noticeable features of such sites.

By studying relevant literature, and analysing a number of existing systems, a number of research challenges are identified and a generic architecture of SQA sites is contributed.

The review contributes a comprehensive knowledge about SQA systems and aims to be helpful to new researchers who want to get a broad picture of SQA systems on a single platform. The domain is in its infancy and requires tremendous efforts from the research community to explore its salient aspects with respect to the human world.

The study inspects SQA sites on a large scale and makes an original contribution by presenting a comprehensive review, future research challenges, and a generic architecture of SQA sites.

Clinical notes typically contain medical jargons and specialized words and phrases that are complicated and technical to most people, which is one of the most challenging obstacles in health information dissemination to consumers by healthcare providers. The authors aim to investigate how to leverage machine learning techniques to transform clinical notes of interest into understandable expressions.

The authors propose a natural language processing pipeline that is capable of extracting relevant information from long unstructured clinical notes and simplifying lexicons by replacing medical jargons and technical terms. Particularly, the authors develop an unsupervised keywords matching method to extract relevant information from clinical notes. To automatically evaluate completeness of the extracted information, the authors perform a multi-label classification task on the relevant texts. To simplify lexicons in the relevant text, the authors identify complex words using a sequence labeler and leverage transformer models to generate candidate words for substitution. The authors validate the proposed pipeline using 58,167 discharge summaries from critical care services.

The results show that the proposed pipeline can identify relevant information with high completeness and simplify complex expressions in clinical notes so that the converted notes have a high level of readability but a low degree of meaning change.

The proposed pipeline can help healthcare consumers well understand their medical information and therefore strengthen communications between healthcare providers and consumers for better care.

An innovative pipeline approach is developed to address the health literacy problem confronted by healthcare providers and consumers in the ongoing digital transformation process in the healthcare industry.