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Article
Publication date: 26 July 2021

Liang Zhang, Liang Jing, Liheng Ye and Xing Gao

This paper aims to investigate the problem of attitude control for a horizontal takeoff and horizontal landing reusable launch vehicle.

426

Abstract

Purpose

This paper aims to investigate the problem of attitude control for a horizontal takeoff and horizontal landing reusable launch vehicle.

Design/methodology/approach

In this paper, a predefined-time attitude tracking controller is presented for a horizontal takeoff and horizontal landing reusable launch vehicle (HTHLRLV). Firstly, the attitude tracking error dynamics model of the HTHLRLV is developed. Subsequently, a novel sliding mode surface is designed with predefined-time stability. Furthermore, by using the proposed sliding mode surface, a predefined-time controller is derived. To compensate the external disturbances or model uncertainties, a fixed-time disturbance observer is developed, and its convergence time can be defined as a prior control parameter. Finally, the stability of the proposed sliding mode surface and the controller can be proved by the Lyapunov theory.

Findings

In contrast to other fixed-time methods, this controller only requires three control parameters, and the convergence time can be predefined instead of being estimated. The simulation results also demonstrate the effectiveness of the proposed controller.

Originality/value

A novel predefined-time attitude tracking controller is developed based on the predefined-time sliding mode surface (SMS) and fixed-time disturbance observer (FxTDO). The convergence time of the system can be selected as a prior control parameter for SMS and FxTDO.

Details

Aircraft Engineering and Aerospace Technology, vol. 93 no. 6
Type: Research Article
ISSN: 1748-8842

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Article
Publication date: 31 May 2022

Feiming Wang, Xing Gao, Shuliang Zang and Shuang Yue

The purpose of this paper is to investigate the tribological properties, antiwear mechanism and anticorrosion properties of two novel halogen-free borate ionic liquids (ILs) in…

95

Abstract

Purpose

The purpose of this paper is to investigate the tribological properties, antiwear mechanism and anticorrosion properties of two novel halogen-free borate ionic liquids (ILs) in 500 N base oil.

Design/methodology/approach

Different qualities of borate ILs were added to 500 N, and their tribological properties were tested on a four-ball machine. The tribological properties of the additives were evaluated by measuring the wear scar diameter (WSD) and average coefficient of friction. The antiwear and antifriction mechanism of ILs was analyzed by energy dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS).

Findings

The corrosion degrees of the two borate ILs 1-butyl-3-octyl-imidazole bis(mandelato)-borate ([OBIM][BMB]) and 1-butyl-3-(3-methoxypropyl)-imidazole bis(mandelato)-borate ([MPBIM][BMB]) are 1b and 1a, respectively, suggesting that they both possess significant corrosion resistance and can effectively protect the steel surface. When the concentration of [OBIM][BMB] and [MPBIM][BMB] is 2.5 Wt.%, the friction coefficient of 500 N is reduced by 37.3% and 26.2%, respectively. According to the analysis of the thermo gravimetric analyzer curves, [OBIM][BMB] and [MPBIM][BMB] decomposed at 369.7°C and 374.3°C, respectively, indicate that two additives both can be applied in higher temperature condition. The results of XPS and scanning electron microscope (SEM) reveal that [OBIM][BMB] and [MPBIM][BMB] both can react with the steel surface, thereby forming chemical films composed of iron oxide, B2O3 and organic N-containing compounds.

Originality/value

Two new environmentally friendly borate ILs were synthesized and their tribological properties in 500 N base oil were investigated for the first time.

Details

Industrial Lubrication and Tribology, vol. 74 no. 6
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 13 April 2023

Xing Gao, Z.J. Zhang, Hong Wei, Xu Zhou, Quan Shi, Yang Wu and Lei Da Chen

Solder bumps for chip interconnections are downsizing from current approximately 100 µm to the expected 1 µm in future. As a result, the Cu-Ni cross-interaction in Cu/Solder/Ni…

121

Abstract

Purpose

Solder bumps for chip interconnections are downsizing from current approximately 100 µm to the expected 1 µm in future. As a result, the Cu-Ni cross-interaction in Cu/Solder/Ni solder joints will be more complicated and then strongly influence the growth of the intermetallic compounds (IMCs). Thus, it is critical to understand the fundamental aspects of interfacial reaction in micro solder joints. This paper aims to reveal the effect mechanism of reflow temperature and solder size on the interfacial reaction in Cu/Solder/Ni solder joints.

Design/methodology/approach

The Cu-Ni cross-interaction in the Cu/Sn/Ni micro solder joints with 50 and 100 µm solder sizes at 250°C and 300°C were observed, respectively. The line-type interconnects were soaked in silicone oil, and the temperature of the line-type interconnects was 250 ± 3°C and 300 ± 3°C, which were monitored by a fine K-type thermocouple, and followed by an isothermal aging process at various times. After aging, the specimens were removed from the silicone oil and cooled in the air to room temperature.

Findings

The major interfacial reaction product on both interfaces was (Cu,Ni)6Sn5, and the asymmetric growth of (Cu,Ni)6Sn5, evidenced by the thickness of (Cu,Ni)6Sn5 IMCs at the Sn/Ni interface was always larger than that at the Sn/Cu interface, resulted from the directional migration of Cu atoms toward the Sn/Ni interface under Cu concentration gradient. The morphology of (Cu,Ni)6Sn5 IMC at Sn/Cu interface was columnlike at 250°C, and which changed from columnlike to scallop with large aspect ratio at 300°C, while that at Sn/Ni interface gradually evolved from needlelike to the mixture of needlelike and layered at 250°C, and which evolved from needlelike to scallop with large aspect ratio at 300°C. The evolution of morphology of (Cu,Ni)6Sn5 is attributed to the content of Ni. Furthermore, the results indicate that the Cu-Ni cross-interaction was stronger with small solder size and relatively low temperature in the Cu/Sn/Ni micro solder joints.

Originality/value

The asymmetric growth of (Cu,Ni)6Sn5 in the Cu/Sn/Ni micro solder joints, evidenced by the thickness of (Cu,Ni)6Sn5 IMCs at the Sn/Ni interface, was always larger than that at the Sn/Cu interface. The morphology evolution of (Cu,Ni)6Sn5 IMC at both interfaces was attributed to the content of Ni. The Cu-Ni cross-interaction was stronger with small solder size and relatively low temperature in the Cu/Sn/Ni micro solder joints.

Details

Microelectronics International, vol. 41 no. 1
Type: Research Article
ISSN: 1356-5362

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Article
Publication date: 28 June 2013

Sheau‐yueh J. Chao

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…

325

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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Article
Publication date: 16 April 2024

Kunpeng Shi, Guodong Jin, Weichao Yan and Huilin Xing

Accurately evaluating fluid flow behaviors and determining permeability for deforming porous media is time-consuming and remains challenging. This paper aims to propose a novel…

110

Abstract

Purpose

Accurately evaluating fluid flow behaviors and determining permeability for deforming porous media is time-consuming and remains challenging. This paper aims to propose a novel machine-learning method for the rapid estimation of permeability of porous media at different deformation stages constrained by hydro-mechanical coupling analysis.

Design/methodology/approach

A convolutional neural network (CNN) is proposed in this paper, which is guided by the results of finite element coupling analysis of equilibrium equation for mechanical deformation and Boltzmann equation for fluid dynamics during the hydro-mechanical coupling process [denoted as Finite element lattice Boltzmann model (FELBM) in this paper]. The FELBM ensures the Lattice Boltzmann analysis of coupled fluid flow with an unstructured mesh, which varies with the corresponding nodal displacement resulting from mechanical deformation. It provides reliable label data for permeability estimation at different stages using CNN.

Findings

The proposed CNN can rapidly and accurately estimate the permeability of deformable porous media, significantly reducing processing time. The application studies demonstrate high accuracy in predicting the permeability of deformable porous media for both the test and validation sets. The corresponding correlation coefficients (R2) is 0.93 for the validation set, and the R2 for the test set A and test set B are 0.93 and 0.94, respectively.

Originality/value

This study proposes an innovative approach with the CNN to rapidly estimate permeability in porous media under dynamic deformations, guided by FELBM coupling analysis. The fast and accurate performance of CNN underscores its promising potential for future applications.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 34 no. 8
Type: Research Article
ISSN: 0961-5539

Keywords

Available. Open Access. Open Access
Article
Publication date: 31 January 2023

Skania Geldres-Weiss, Inés Küster-Boluda and Natalia Vila-López

This paper studies, based on the theory of service-dominant logic, the effect of value co-creation practices (linking and materializing) on engagement dimensions (popularity…

1954

Abstract

Purpose

This paper studies, based on the theory of service-dominant logic, the effect of value co-creation practices (linking and materializing) on engagement dimensions (popularity, commitment and virality). The main objective is to analyze the influence of value co-creation practices on engagement at international trade shows organizer association on Twitter.

Design/methodology/approach

This paper studies the usage of Twitter by the Specialty Food Association, which organizes one of the top five foods and beverage international trade show in the United States. To achieve the research objective, the authors have analyzed 1,608 posts on Twitter from the Twitter account @Specialty_Food. A content analysis was performed using Krippendorff's (2004) recommendations, and the data were analyzed using regression analysis with optimal scaling and Kruskal–Wallis Test.

Findings

According to the results, some materializing practices influence popularity, commitment, virality and global engagement on Twitter. While the usage of some linking practices influences respectively commitment and popularity.

Originality

These results provide valuable information for business-to-business (B2B) contexts and answer a research gap reported in previous literature, which affirms that more research is needed about the relationship between service systems and engagement. From a general view, to generate more engagement on social media in B2B contexts, it is recommended to prioritize posts that incorporate live and online events based on collaborative and dynamic human interactions, following by business ideas and business cases.

Details

European Journal of Management and Business Economics, vol. 32 no. 3
Type: Research Article
ISSN: 2444-8451

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Article
Publication date: 23 January 2009

Xing Gao, Ming‐Hong Liao, Xiang‐Hu Wu and Chao‐Yong Li

The purpose of this paper is to present a novel algorithm to handle space environment induced errors in the space‐robot software.

410

Abstract

Purpose

The purpose of this paper is to present a novel algorithm to handle space environment induced errors in the space‐robot software.

Design/methodology/approach

The radiations in outer space may induce transient errors in micro‐processors, this phenomena will make software behavior unpredictable, and the existing software fault tolerance methods have been restricted in non‐multi‐threaded operation systems, non‐component‐based frameworks, non‐cacheable micro‐processors, non‐distributed environments, etc. A software model for space‐robot software, based on adaptive redundancy, is developed and a corresponding run‐time error detection algorithm is presented in this paper. Software was monitored and run‐time transient error would be detected and processed.

Findings

Experiments indicate that this method introduces about 30‐35 percent time overhead and about 200‐230 percent memory overhead. It also increases the fault detection rate to 84‐92.5 percent. Moreover, the model and algorithm is effective in a realistic space robot environment.

Originality/value

A redundancy model is developed and an error detection algorithm is introduced in this paper. Experiments demonstrate it can provide space‐robot software with good protection against the radiation induced transient errors.

Details

Aircraft Engineering and Aerospace Technology, vol. 81 no. 1
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 9 February 2018

Arshad Ahmad, Chong Feng, Shi Ge and Abdallah Yousif

Software developers extensively use stack overflow (SO) for knowledge sharing on software development. Thus, software engineering researchers have started mining the…

1796

Abstract

Purpose

Software developers extensively use stack overflow (SO) for knowledge sharing on software development. Thus, software engineering researchers have started mining the structured/unstructured data present in certain software repositories including the Q&A software developer community SO, with the aim to improve software development. The purpose of this paper is show that how academics/practitioners can get benefit from the valuable user-generated content shared on various online social networks, specifically from Q&A community SO for software development.

Design/methodology/approach

A comprehensive literature review was conducted and 166 research papers on SO were categorized about software development from the inception of SO till June 2016.

Findings

Most of the studies revolve around a limited number of software development tasks; approximately 70 percent of the papers used millions of posts data, applied basic machine learning methods, and conducted investigations semi-automatically and quantitative studies. Thus, future research should focus on the overcoming existing identified challenges and gaps.

Practical implications

The work on SO is classified into two main categories; “SO design and usage” and “SO content applications.” These categories not only give insights to Q&A forum providers about the shortcomings in design and usage of such forums but also provide ways to overcome them in future. It also enables software developers to exploit such forums for the identified under-utilized tasks of software development.

Originality/value

The study is the first of its kind to explore the work on SO about software development and makes an original contribution by presenting a comprehensive review, design/usage shortcomings of Q&A sites, and future research challenges.

Details

Data Technologies and Applications, vol. 52 no. 2
Type: Research Article
ISSN: 2514-9288

Keywords

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Book part
Publication date: 7 December 2023

Mikael Johnsson

It is suggested that, to be successful, innovation teams should be small and consist of people with key expertise who want to participate and develop new solutions within their…

Abstract

It is suggested that, to be successful, innovation teams should be small and consist of people with key expertise who want to participate and develop new solutions within their organisations. When it comes to conducting innovation work, I suggest shared leadership may be a factor influencing success. In this chapter, a theoretical framework is presented on the shared leadership of innovation teams. The key to establishing shared leadership in innovation teams is to plan for it as the team is created, not after the team has already been formed, as this may result in various problems in the intended innovation project. The proposed framework details key aspects to consider; some of which are related to external factors such as management and resources, and some to internal factors such as the team’s size, competencies, and their ability to develop norms and ways of working together. The proposed framework is applicable for managers, innovation leaders, and team members, and contributes to previous research on shared leadership and innovation leadership. Further research on the proposed framework is suggested.

Details

Innovation Leadership in Practice: How Leaders Turn Ideas into Value in a Changing World
Type: Book
ISBN: 978-1-83753-397-8

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Article
Publication date: 24 December 2024

Feliza Marie Santos Mercado and Sungwon Shin

In response to challenges in traditional professional development, educators are increasingly utilizing social media platforms to customize their learning experiences and…

39

Abstract

Purpose

In response to challenges in traditional professional development, educators are increasingly utilizing social media platforms to customize their learning experiences and facilitate their professional growth. This systematic literature review seeks to examine articles published between January 2018 and July 2023 to synthesize evidence on the ways in which teachers are leveraging social media to improve their teaching practices.

Design/methodology/approach

The authors used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) to guide the literature review process. First, the authors established synthesis questions, set up eligibility criteria and determined search engines and search terms to identify the relevant literature. Second, the authors sorted and selected from the preliminary article search and screened based on the established criteria. Finally, the authors analyzed each selected article’s content, which included coding, interpreting the themes and organizing the findings.

Findings

Teachers are increasingly using social media for professional development, engaging in collaboration, empowering connection, and relationship-building through teacherpreneurship. They take on various roles, from info-consumers and info-networkers to self-seeking contributors, vocationalists and lurkers. Despite these benefits, challenges remain, such as potential for unexpected misunderstandings, social comparison that can lead to low self-esteem, which can hinder effective engagement in social media-based professional development. Additionally, this paper observed a growing trend in scholarly articles on this topic, particularly from 2020, 2021 and 2022, highlighting its increasing relevance and impact on the educational community.

Research limitations/implications

This systematic literature review focused exclusively on studies involving in-service K-12 teachers as participants, excluding perspectives from preservice teachers, higher education instructors, instructional coaches and school administrators. While these other educational professionals undoubtedly offer valuable insights into improving teaching practices and contribute significantly to social media-based professional development, this review aimed to center the experiences of K-12 in-service teachers to understand their unique professional development needs and practices. Consequently, it does not capture the potential synergies between K-12 teachers and other educator groups, such as the ways in which school administrators might support or enhance in-service teachers’ professional development through social media. Future studies could explore these interactions more deeply to provide a fuller picture of the collective expertise within these groups.

Practical implications

The COVID-19 pandemic underscored the value of social media for informal professional development, as shown by the increased number of publications on this topic during that period. However, some social media platforms prioritize consumerism over educational resources, emphasizing the need for educators to critically evaluate their sources. Teachers should be discerning in their resource selection, ensuring that educational references are credible and free of hidden costs.

Social implications

This study uncovered several unique patterns in how teachers use social media, revealing both benefits and challenges. Notably, some teachers are leveraging social media not only to build professional connections but also to engage in commercial activities. While this practice can create a supportive network – where teachers promote one another’s visibility, share products and seek support – it can also detract from the intended purpose of professional learning. The focus on brand-building and profit-making may overshadow authentic community-building and collaborative growth. Additionally, the presence of paid content introduces financial barriers, as many teachers have limited resources for professional development.

Originality/value

This study provides a comprehensive review of recent literature (January 2018 to July 2023) on teachers' use of social media for professional development and learning, offering fresh insights into emerging trends. Notably, findings of this study highlight the role of teacherpreneurship in fostering beneficial social connections within digital spaces, a factor that has gained prominence as teachers seek collaborative and supportive networks. Additionally, this research sheds light on lurking as a common strategy among teachers to avoid conflict and misunderstandings when engaging in social media-based professional development. Furthermore, by addressing various challenges, this paper presents suggestions for thoughtfully integrating social media into school professional development programs, with the intention of supporting the diverse needs of teachers and fostering their professional growth.

Details

Information and Learning Sciences, vol. 126 no. 3/4
Type: Research Article
ISSN: 2398-5348

Keywords

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