Mauricio E. Pilleux, Ahmad Safari, Mehdi Allahverdi, Youren Chen, Yicheng Lu and Mohsen A. Jafari
Three‐dimensional photonic bandgap (PBG) structures using alumina (Al2O3) as the high permittivity material were modeled and then the structures were fabricated by Fused…
Abstract
Three‐dimensional photonic bandgap (PBG) structures using alumina (Al2O3) as the high permittivity material were modeled and then the structures were fabricated by Fused Deposition of Multi‐materials (FDMM) technology. A finite element method and a real‐time electromagnetic wave propagation software were used to simulate and design the layered PBG structures for applications in the microwave frequency range. The modeling predicted a 3‐D photonic bandgap in the 16.5–23.5 GHz range. FDMM provides a computer‐controlled process to generate 3‐D structures, allowing high fabrication flexibility and efficiency. Electromagnetic measurements displayed the presence of a bandgap between 17.1–23.3 GHz, showing a good agreement with the predicted values. These PBG structures are potential candidates for applications in advanced communication systems.
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Qin Kang, Yicheng Fan, Kun Zhang, Xiaolang Chen, Hongyu San, Yiqing Chen and Heming Zhao
With excellent mechanic properties and hydrogen embrittlement (HE) resistance, 12Cr2Mo1R(H) steel is suitable to make hot-wall hydrogenation reactors. However, longtime exposure…
Abstract
Purpose
With excellent mechanic properties and hydrogen embrittlement (HE) resistance, 12Cr2Mo1R(H) steel is suitable to make hot-wall hydrogenation reactors. However, longtime exposure to a harsh environment of high-pressure hydrogen at medium temperature in practical application would still induce severe hydrogen uptake and eventually damage the mechanical properties of the steel. The study aims to evaluate the HE resistance of the steel under different tensile strain rates after hydrogen charging and analyze the hydrogen effect from atomic level.
Design/methodology/approach
This research studied the HE properties of 12Cr2Mo1R(H) steel by slow strain rate tests. Meanwhile, the effect of hydrogen on the structures and the mechanical properties of the simplified models of the steel was also investigated by first-principle calculations.
Findings
Experimental results showed that after hydrogen pre-charging in this work, hydrogen had little effect on the microstructure of the steel. The elongations and reduction of cross-sectional area of the samples reduced a lot, by contrast, the yield and tensile strengths changed slightly. The 12Cr2Mo1R(H) steel was not very susceptible to HE with a maximum embrittlement index of about 20.00%. First principles calculation results showed that after H dissolution, lattice distortion occurred and interstitial H atoms would preferentially occupy the tetrahedral interstitial site in bcc-Fe crystal and increase the stability of the supercells. With the increase of H atoms added into the simplified model, the steel still possessed a good ductility and toughness at a low hydrogen concentration, while the material would become brittle as the concentration of hydrogen continued to increase.
Originality/value
These finds can provide valuable information for subsequent HE studies on this steel.
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Xiang Qiu, Kun Zhang, Qin Kang, Yicheng Fan, Hongyu San, Yiqing Chen and Heming Zhao
This paper aims to study the mechanism of hydrogen embrittlement in 12Cr2Mo1R(H) steel, which will help to provide valuable information for the subsequent hydrogen embrittlement…
Abstract
Purpose
This paper aims to study the mechanism of hydrogen embrittlement in 12Cr2Mo1R(H) steel, which will help to provide valuable information for the subsequent hydrogen embrittlement research of this kind of steel, so as to optimize the processing technology and take more appropriate measures to prevent hydrogen damage.
Design/methodology/approach
The hydrogen diffusion coefficient of 12Cr2Mo1R(H) steel was measured by the hydrogen permeation technique of double electrolytic cells. Moreover, the influence of hydrogen traps in the material and experimental temperature on hydrogen diffusion behavior was discussed. The first-principles calculations based on density functional theory were used to study the occupancy of H atoms in the bcc-Fe cell, the diffusion path and the interaction with vacancy defects.
Findings
The results revealed that the logarithm of the hydrogen diffusion coefficient of the material has a linear relationship with the reciprocal of temperature and the activation energy of hydrogen atom diffusion in 12Cr2Mo1R(H) steel is 23.47 kJ/mol. H atoms stably exist in the nearly octahedral interstices in the crystal cell with vacancies. In addition, the solution of Cr/Mo alloy atom does not change the lowest energy path of H atom, but increases the diffusion activation energy of hydrogen atom, thus hindering the diffusion of hydrogen atom. Cr/Mo and vacancy have a synergistic effect on inhibiting the diffusion of H atoms in α-Fe.
Originality/value
This article combines experiments with first-principles calculations to explore the diffusion behavior of hydrogen in 12Cr2Mo1R(H) steel from the macroscopic and microscopic perspectives, which will help to establish a calculation model with complex defects in the future.
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The purpose of this paper is to explore how variations in management’s tone within management’s discussion and analysis (MD&A) sections of 10-K reports can serve as an indicator…
Abstract
Purpose
The purpose of this paper is to explore how variations in management’s tone within management’s discussion and analysis (MD&A) sections of 10-K reports can serve as an indicator of tax avoidance and highlight the complex relationship between such linguistic shifts and the tax avoidance decisions within firms.
Design/methodology/approach
The paper uses a textual analysis approach to identify linguistic cues in MD&A sections of 10-K filings related to tax avoidance, going beyond traditional quantitative measures. The study uses differences in negative word occurrences in MD&A to measure management’s tone change and examines various measures of tax avoidance. The sample covers the period from 1993 to 2017 and comprises all firms with 10-K filings available on EDGAR, totaling over 30,000 firm-year observations.
Findings
The findings indicate a complementary relationship between tax avoidance and other drivers of firm performance. When firms have more negative management’s tone, they are less willing to engage in tax avoidance and vice versa. The study’s approach with management’s tone change provides a different and statistically significant improvement in model fit for detecting tax avoidance.
Practical implications
This paper provides actionable insights for detecting tax avoidance through the analysis of management’s tone in corporate disclosures, offering a new tool for researchers, investors and tax authorities. It highlights the importance of linguistic cues as indicators of tax avoidance behavior, complementing traditional financial metrics.
Originality/value
The paper contributes to the literature by using management’s tone change as a time-varying factor to explain tax avoidance behavior. It uncovers a larger set of linguistic cues in MD&A that can be used to detect tax avoidance. This research provides a complementary approach to traditional quantitative tax avoidance measures and offers insights into the overall relationship between tax avoidance and firm performance, going beyond one-dimensional measures typically used in prior literature.
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Xingwei Li, Xiang Liu, Yicheng Huang, Jingru Li, Jinrong He and Jiachi Dai
The green innovation behavior of construction enterprises is the key to reducing the construction industry's carbon emissions and realizing the green transformation of the…
Abstract
Purpose
The green innovation behavior of construction enterprises is the key to reducing the construction industry's carbon emissions and realizing the green transformation of the construction industry. The purpose of this study is to reveal the evolutionary mechanism of green innovation behavior in construction enterprises.
Design/methodology/approach
This study is based on resource-based theory, Porter's hypothesis and signaling theory. First, a measurement model of the green innovation behavior of construction enterprises was constructed from three aspects: environmental regulation, enterprise resources and public opinion through hierarchical analysis. Then, the state values of the measurement model of green innovation behavior of construction enterprises were calculated through the time series data from 2011–2018. Finally, the Markov chain model was used to predict the evolutionary trend of green innovation behavior of construction enterprises, and the accuracy of the prediction effect of the Markov chain model was verified using the time series data of 2019.
Findings
The Markov chain model of green innovation behavior of construction enterprises constructed in this study has high accuracy. This model finds that the transition of the growth state of green innovation behavior in China's construction industry is fluid and predicts the evolution trend of the innovation behavior of construction enterprises. In the future, the green innovation behavior of construction enterprises has a probability of 70.17% to be in a continuous growth state and 40.27% to be in a rapid growth state.
Originality/value
Based on the Markov chain model of green innovation behavior of construction enterprises, this study finds that the transition of the growth state of green innovation behavior of construction enterprises in China has the characteristics of liquidity. In addition, it reveals the development process of the green innovation behavior of construction enterprises from 2011–2018 and predicts the evolution trend of the green innovation behavior of construction enterprises.
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Prefabricated housing is a construction method that largely reduces construction waste and promotes sustainable development. However, the adoption of this method of construction…
Abstract
Purpose
Prefabricated housing is a construction method that largely reduces construction waste and promotes sustainable development. However, the adoption of this method of construction is inhibited by the lack of demand by consumers. The purpose of this research is to explore consumer education strategies aimed at overcoming prefabricated housing challenges in China.
Design/methodology/approach
The study conducted a systematic literature review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A comprehensive search was conducted using databases such as Scopus and Web of Science, without any restriction on publication date. A total of 33 relevant articles were retrieved and analyzed using the content analysis method. The findings were then summarized and presented using the tabulation technique.
Findings
This study identified several barriers to prefabricated housing, including negative perception, limited public understanding, risk-averse culture and lack of green value. To foster market demand, relevant authorities should consider implementing effective educational mechanisms, such as comparative advertising, social media marketing, school programs and critical adult education programs. These strategies can effectively overcome the existing negative perception, alleviate concerns and create a positive environment for the growth of prefabricated housing in China.
Originality/value
This research provides practical and theoretical implications by identifying key challenges to prefabricated housing and suggesting targeted educational strategies to address them. It offers valuable guidance for policymakers, industry stakeholders and researchers, contributing to the advancement of sustainable housing practices.
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The purpose of this paper is to provide the historical background of genealogical records and analyze the value of Chinese genealogical research through the study of names and…
Abstract
Purpose
The purpose of this paper is to provide the historical background of genealogical records and analyze the value of Chinese genealogical research through the study of names and genealogical resources.
Design/methodology/approach
The paper examines the historical evolution and value of Chinese genealogical records, with the focus on researching the Islamic Chinese names used by the people living in Guilin. The highlight of this paper includes the analysis and evolution of the Islamic Chinese names commonly adopted by the local people in Guilin. It concludes with the recommendations on emphasizing and making the best use of genealogical records to enhance the research value of Chinese overseas studies.
Findings
The paper covers the history of Islam and describes how the religion was introduced into China, as well as Muslims' ethnicity and identity. It also places focus on the importance of building a research collection in Asian history and Chinese genealogy.
Research limitations/implications
This research study has a strong subject focus on Chinese genealogy, Asian history, and Islamic Chinese surnames. It is a narrow field that few researchers have delved into.
Practical implications
The results of this study will assist students, researchers, and the general public in tracing the origin of their surnames and developing their interest in the social and historical value of Chinese local history and genealogies.
Social implications
The study of Chinese surnames is, by itself, a particular field for researching the social and political implications of contemporary Chinese society during the time the family members lived.
Originality/value
Very little research has been done in the area of Chinese local history and genealogy. The paper would be of value to researchers such as historians, sociologists, ethnologists and archaeologists, as well as students and anyone interested in researching a surname origin, its history and evolution.
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Kevin Wang and Peter Alexander Muennig
The study explores how Taiwan’s electronic health data systems can be used to build algorithms that reduce or eliminate medical errors and to advance precision medicine.
Abstract
Purpose
The study explores how Taiwan’s electronic health data systems can be used to build algorithms that reduce or eliminate medical errors and to advance precision medicine.
Design/methodology/approach
This study is a narrative review of the literature.
Findings
The body of medical knowledge has grown far too large for human clinicians to parse. In theory, electronic health records could augment clinical decision-making with electronic clinical decision support systems (CDSSs). However, computer scientists and clinicians have made remarkably little progress in building CDSSs, because health data tend to be siloed across many different systems that are not interoperable and cannot be linked using common identifiers. As a result, medicine in the USA is often practiced inconsistently with poor adherence to the best preventive and clinical practices. Poor information technology infrastructure contributes to medical errors and waste, resulting in suboptimal care and tens of thousands of premature deaths every year. Taiwan’s national health system, in contrast, is underpinned by a coordinated system of electronic data systems but remains underutilized. In this paper, the authors present a theoretical path toward developing artificial intelligence (AI)-driven CDSS systems using Taiwan’s National Health Insurance Research Database. Such a system could in theory not only optimize care and prevent clinical errors but also empower patients to track their progress in achieving their personal health goals.
Originality/value
While research teams have previously built AI systems with limited applications, this study provides a framework for building global AI-based CDSS systems using one of the world’s few unified electronic health data systems.