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Article
Publication date: 9 February 2024

Chengpeng Zhang, Zhihua Yu, Jimin Shi, Yu Li, Wenqiang Xu, Zheyi Guo, Hongshi Zhang, Zhongyuan Zhu and Sheng Qiang

Hexahedral meshing is one of the most important steps in performing an accurate simulation using the finite element analysis (FEA). However, the current hexahedral meshing method…

Abstract

Purpose

Hexahedral meshing is one of the most important steps in performing an accurate simulation using the finite element analysis (FEA). However, the current hexahedral meshing method in the industry is a nonautomatic and inefficient method, i.e. manually decomposing the model into suitable blocks and obtaining the hexahedral mesh from these blocks by mapping or sweeping algorithms. The purpose of this paper is to propose an almost automatic decomposition algorithm based on the 3D frame field and model features to replace the traditional time-consuming and laborious manual decomposition method.

Design/methodology/approach

The proposed algorithm is based on the 3D frame field and features, where features are used to construct feature-cutting surfaces and the 3D frame field is used to construct singular-cutting surfaces. The feature-cutting surfaces constructed from concave features first reduce the complexity of the model and decompose it into some coarse blocks. Then, an improved 3D frame field algorithm is performed on these coarse blocks to extract the singular structure and construct singular-cutting surfaces to further decompose the coarse blocks. In most modeling examples, the proposed algorithm uses both types of cutting surfaces to decompose models fully automatically. In a few examples with special requirements for hexahedral meshes, the algorithm requires manual input of some user-defined cutting surfaces and constructs different singular-cutting surfaces to ensure the effectiveness of the decomposition.

Findings

Benefiting from the feature decomposition and the 3D frame field algorithm, the output blocks of the proposed algorithm have no inner singular structure and are suitable for the mapping or sweeping algorithm. The introduction of internal constraints makes 3D frame field generation more robust in this paper, and it can automatically correct some invalid 3–5 singular structures. In a few examples with special requirements, the proposed algorithm successfully generates valid blocks even though the singular structure of the model is modified by user-defined cutting surfaces.

Originality/value

The proposed algorithm takes the advantage of feature decomposition and the 3D frame field to generate suitable blocks for a mapping or sweeping algorithm, which saves a lot of simulation time and requires less experience. The user-defined cutting surfaces enable the creation of special hexahedral meshes, which was difficult with previous algorithms. An improved 3D frame field generation method is proposed to correct some invalid singular structures and improve the robustness of the previous methods.

Details

Engineering Computations, vol. 41 no. 1
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 12 January 2024

Imtiyaz Ahmad Bhat, Lakshmi Narayan Mishra, Vishnu Narayan Mishra, Cemil Tunç and Osman Tunç

This study aims to discuss the numerical solutions of weakly singular Volterra and Fredholm integral equations, which are used to model the problems like heat conduction in…

Abstract

Purpose

This study aims to discuss the numerical solutions of weakly singular Volterra and Fredholm integral equations, which are used to model the problems like heat conduction in engineering and the electrostatic potential theory, using the modified Lagrange polynomial interpolation technique combined with the biconjugate gradient stabilized method (BiCGSTAB). The framework for the existence of the unique solutions of the integral equations is provided in the context of the Banach contraction principle and Bielecki norm.

Design/methodology/approach

The authors have applied the modified Lagrange polynomial method to approximate the numerical solutions of the second kind of weakly singular Volterra and Fredholm integral equations.

Findings

Approaching the interpolation of the unknown function using the aforementioned method generates an algebraic system of equations that is solved by an appropriate classical technique. Furthermore, some theorems concerning the convergence of the method and error estimation are proved. Some numerical examples are provided which attest to the application, effectiveness and reliability of the method. Compared to the Fredholm integral equations of weakly singular type, the current technique works better for the Volterra integral equations of weakly singular type. Furthermore, illustrative examples and comparisons are provided to show the approach’s validity and practicality, which demonstrates that the present method works well in contrast to the referenced method. The computations were performed by MATLAB software.

Research limitations/implications

The convergence of these methods is dependent on the smoothness of the solution, it is challenging to find the solution and approximate it computationally in various applications modelled by integral equations of non-smooth kernels. Traditional analytical techniques, such as projection methods, do not work well in these cases since the produced linear system is unconditioned and hard to address. Also, proving the convergence and estimating error might be difficult. They are frequently also expensive to implement.

Practical implications

There is a great need for fast, user-friendly numerical techniques for these types of equations. In addition, polynomials are the most frequently used mathematical tools because of their ease of expression, quick computation on modern computers and simple to define. As a result, they made substantial contributions for many years to the theories and analysis like approximation and numerical, respectively.

Social implications

This work presents a useful method for handling weakly singular integral equations without involving any process of change of variables to eliminate the singularity of the solution.

Originality/value

To the best of the authors’ knowledge, the authors claim the originality and effectiveness of their work, highlighting its successful application in addressing weakly singular Volterra and Fredholm integral equations for the first time. Importantly, the approach acknowledges and preserves the possible singularity of the solution, a novel aspect yet to be explored by researchers in the field.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 34 no. 3
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 13 November 2023

Maryam Mohseni and Davood Rostamy

The numerical methods are of great importance for approximating the solutions of a system of nonlinear singular ordinary differential equations. In this paper, the authors present…

Abstract

Purpose

The numerical methods are of great importance for approximating the solutions of a system of nonlinear singular ordinary differential equations. In this paper, the authors present the biorthogonal flatlet multiwavelet collocation method (BFMCM) as a numerical scheme for a class of system of Lane–Emden equations with initial or boundary or four-point boundary conditions.

Design/methodology/approach

The approach is involved in combining the biorthogonal flatlet multiwavelet (BFM) with the collocation method. The authors investigate the properties and procedure of the BFMCM for first time on this class of equations. By using the BFM and the collocation points, the method is constructed and it transforms the nonlinear differential equations problem into a system of nonlinear algebraic equations. The unknown coefficients of the assuming solution are determined by solving the obtained system. Additionally, convergence analysis and numerical stability of the suggested method are provided.

Findings

According to the attained results, the proposed BFMCM has more accurate results in comparison with results of other methods. The maximum absolute errors are calculated by using the BFMCM for comparison purposes provided.

Originality/value

The key desirable properties of BFMCM are its efficiency, simple applicability and minimizes errors. Therefore, the proposed method can be used to solve nonlinear problems or problems with singular points.

Details

Engineering Computations, vol. 40 no. 9/10
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 15 February 2024

Quanwei Yin, Liang Zhang and Xudong Zhao

This paper aims to study the issues of output reachable set estimation for the linear singular Markovian jump systems (SMJSs) with time-varying delay based on a proportional plus…

Abstract

Purpose

This paper aims to study the issues of output reachable set estimation for the linear singular Markovian jump systems (SMJSs) with time-varying delay based on a proportional plus derivative (PD) bumpless transfer (BT) output feedback (OF) control scheme.

Design/methodology/approach

To begin with, a sufficient criterion is given in the form of a linear matrix inequality based on the Lyapunov stability theory. Then, a PD-BT OF controller is designed to keep all the output signs of the system are maintain within a predetermined ellipsoid. Finally, numerical and practical examples are used to demonstrate the efficiency of the approach.

Findings

Based on PD control and BT control method, an OF control strategy for the linear SMJSs with time-varying delay is proposed.

Originality/value

The output reachable set synthesis of linear SMJSs with time-varying delay can be solved by using the proposed approach. Besides, to obtain more general results, the restrictive assumptions of some parameters are removed. Furthermore, a sufficiently small ellipsoid can be obtained by the design scheme adopted in this paper, which reduces the conservatism of the existing results.

Details

Robotic Intelligence and Automation, vol. 44 no. 1
Type: Research Article
ISSN: 2754-6969

Keywords

Article
Publication date: 5 February 2024

Elena Fedorova, Alexandr Nevredinov and Pavel Drogovoz

The purpose of our study is to study the impact of chief executive officer (CEO) optimism and narcissism on the company's capital structure.

Abstract

Purpose

The purpose of our study is to study the impact of chief executive officer (CEO) optimism and narcissism on the company's capital structure.

Design/methodology/approach

(1) The authors opt for regression, machine learning and text analysis to explore the impact of narcissism and optimism on the capital structure. (2) We analyze CEO interviews and employ three methods to evaluate narcissism: the dictionary proposed by Anglin, which enabled us to assess the following components: authority, superiority, vanity and exhibitionism; count of first-person singular and plural pronouns and count of CEO photos displayed. Following this approach, we were able to make a more thorough assessment of corporate narcissism. (3) Latent Dirichlet allocation (LDA) technique helped to find the differences in the corporate rhetoric of narcissistic and non-narcissistic CEOs and to find differences between the topics of interviews and letters provided by narcissistic and non-narcissistic CEOs.

Findings

Our research demonstrates that narcissism has a slight and nonlinear impact on capital structure. However, our findings suggest that there is an impact of pessimism and uncertainty under pandemic conditions when managers predicted doom and completely changed their strategies. We applied various approaches to estimate the gender distribution of CEOs and found that the median values of optimism and narcissism do not depend on sex. Using LDA, we examined the content and key topics of CEO interviews, defined as positive and negative. There are some differences in the topics: narcissistic CEOs are more likely to speak about long-term goals, projects and problems; they often talk about their brand and business processes.

Originality/value

First, we examine the COVID-19 pandemic period and evaluate how CEO optimism and pessimism affect their financial decisions under specific external conditions. The pandemic forced companies to shift the way they worked: either to switch to the remote work model or to interrupt operations; to lose or, on the contrary, attract clients. In addition, during this period, corporate management can have a different outlook on their company’s financial performance and goals. The LDA technique helped to find the differences in the corporate rhetoric of narcissistic and non-narcissistic CEOs. Second, we use three methods to evaluate narcissism. Third, the research is based on a set of advanced methods: machine learning techniques (random forest to reveal a nonlinear impact of CEO optimism and narcissism on capital structure).

Details

Review of Behavioral Finance, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1940-5979

Keywords

Article
Publication date: 30 January 2024

Abdul-Majid Wazwaz

The purpose of this paper is to investigate a variety of Painlevé integrable equations derived from a Hamiltonian equation.

Abstract

Purpose

The purpose of this paper is to investigate a variety of Painlevé integrable equations derived from a Hamiltonian equation.

Design/methodology/approach

The newly developed Painlevé integrable equations have been handled by using Hirota’s direct method. The authors obtain multiple soliton solutions and other kinds of solutions for these six models.

Findings

The developed Hamiltonian models exhibit complete integrability in analogy with the original equation.

Research limitations/implications

The present study is to address these two main motivations: the study of the integrability features and solitons and other useful solutions for the developed equations.

Practical implications

The work introduces six Painlevé-integrable equations developed from a Hamiltonian model.

Social implications

The work presents useful algorithms for constructing new integrable equations and for handling these equations.

Originality/value

The paper presents an original work with newly developed integrable equations and shows useful findings.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 34 no. 4
Type: Research Article
ISSN: 0961-5539

Keywords

Open Access
Article
Publication date: 27 June 2023

Godspower Ugboh

First, this paper aims to identify and discuss the paradoxical relationship between theology and technology. Second, it also demonstrates the urgency of the digitalization of the…

2281

Abstract

Purpose

First, this paper aims to identify and discuss the paradoxical relationship between theology and technology. Second, it also demonstrates the urgency of the digitalization of the Church ministry. Third, this paper offers an understanding of technology and theology through the missional perspective of the Church. Fourth, this paper asks the following questions: (1) Can the Church innovate ways of using technology while maintaining the social aspect of the organism? (2) Can organizations migrate to digital technology with adequate technology/human interface to engage innovations? (3) How can organizations renew their products via technological platforms? (4) From a socio-technical perspective on the digital era, can the Church keep abreast of its workforce in a way that provides adequate participative opportunities? and finally, this paper further interacts with views on the paradigm shift of practical theology and techno-theological practice and possible inclusion in the theology vocabularies of the Church.

Design/methodology/approach

A thorough search on the subject of techno-theology (TTheo) reveals that there are no scholarly works that offer a conceptual understanding of TTheo. However, TTheo derives an interdisciplinary definition from innovative leadership, socio-religious transformation, transformational leadership, anthropological studies, strategic leadership (and authentic leader AL), scenario thinking/planning, technological disruptions, digital transformation and Church sustainability. There are multiple inferences in the literature on the advantages and disadvantages of technology in human relations (Banks et al., 2016; Dyer, 2011).

Findings

Innovation is open-ended. It can take place anywhere and anytime. All it requires are human entities who are creative enough to respond appropriately. The author agrees with Goldsmith that innovation is not limited to a single aspect of any system (Goldsmith et al., 2010, p. xxiv). Innovation can occur anywhere, and there is no limit to it. The only hindrance to innovation is the lack of creative leaders, creative agents of change and an enabling environment to foster change (Teece, 2018, 2010; Bounfour, 2016; Hanna, 2016). While technological innovation is a good development, other factors drive innovation. Technological innovation is not an end by itself. It is a means to an end. And it cannot stand in isolation from other factors that support it. It competes with some external factors which can sustain it or obstruct it.

Research limitations/implications

This paper used the traditional (or narrative), meta-analysis and meta-synthesis methods of literature reviews to study scenario thinking, system thinking, planning and TTheo principles to find a suitable space to redefine and reconstruct the Church’s ministry engagement in a technologically avowed age. This paper is not a technology text, nor does it pose to answer technology questions. Instead, it focuses on the role of technology in Christian ministry.

Practical implications

This paper recommended that the Church redefines its digital transformation perspective by adopting a TTheo that embraces digital materials and hybrid technology in its ministry engagement across the board. This paper further interacts with views on the paradigm shift of practical theology and techno-theological practice and possible inclusion in the theology vocabularies of the Church.

Social implications

Technology shapes human interactions in a sociopolitical, socioreligious and sociocultural environment (Dyer, 2011; Postman, 2021; McLauhan, 1994, p. 7). As a community of faith, the Church is a segment of the broader cultural environment with a cross-section of people from various works of life and opinions. Language, customs and practice differ significantly from others in every environment. Hence, each setting is unique in multiple ways (Teece, 2018, 2010). The world continues to experience developments in many areas. Due to the symbiotic nature of humans and the environment, cross-breeding and cross-fertilization of ideas are inevitable. As one organization reacts to its unique existence, it indirectly or directly affects another. Hence, while growth may be relative, its impacts are overtly universal.

Originality/value

The term “Techno-theology” is a newcomer in the theological circle. Hence, there are practically little or minimal literature on this subject area. In this paper, the author has written the original concept of the subject matter (TTheo). This paper is part of the ground-breaking research the author is conducting on “Techno-theology.” The author’s PhD research proposal was approved in December 2022. The author’s research focuses on the subject matter of this paper (TTheo). The author also looks forward to leading a deeper conversation among scholars.

Details

Journal of Ethics in Entrepreneurship and Technology, vol. 3 no. 2
Type: Research Article
ISSN: 2633-7436

Keywords

Book part
Publication date: 19 April 2024

Lars Mjøset, Roel Meijer, Nils Butenschøn and Kristian Berg Harpviken

This study employs Stein Rokkan's methodological approach to analyse state formation in the Greater Middle East. It develops a conceptual framework distinguishing colonial…

Abstract

This study employs Stein Rokkan's methodological approach to analyse state formation in the Greater Middle East. It develops a conceptual framework distinguishing colonial, populist and democratic pacts, suitable for analysis of state formation and nation-building through to the present period. The framework relies on historical institutionalism. The methodology, however, is Rokkan's. The initial conceptual analysis also specifies differences between European and the Middle Eastern state formation processes. It is followed by a brief and selective discussion of historical preconditions. Next, the method of plotting singular cases into conceptual-typological maps is applied to 20 cases in the Greater Middle East (including Afghanistan, Iran and Turkey). For reasons of space, the empirical analysis is limited to the colonial period (1870s to the end of World War 1). Three typologies are combined into one conceptual-typological map of this period. The vertical left-hand axis provides a composite typology that clarifies cultural-territorial preconditions. The horizontal axis specifies transformations of the region's agrarian class structures since the mid-19th century reforms. The right-hand vertical axis provides a four-layered typology of processes of external intervention. A final section presents selected comparative case reconstructions. To the authors' knowledge, this is the first time such a Rokkan-style conceptual-typological map has been constructed for a non-European region.

Details

A Comparative Historical and Typological Approach to the Middle Eastern State System
Type: Book
ISBN: 978-1-83753-122-6

Keywords

Book part
Publication date: 12 December 2023

Rebekka J. Jez

Although special education was built upon the foundation of the Civil Rights Act of 1964, the discrimination that many racialized students receiving special education services…

Abstract

Although special education was built upon the foundation of the Civil Rights Act of 1964, the discrimination that many racialized students receiving special education services experience cannot be denied. Many culturally, ethnically, and linguistically diverse students receiving special education services encounter labels that perpetuate racism and ableism and lead to inequitable access to services and resources necessary for more positive postsecondary outcomes. By honoring intersectionality and dismantling the singular identity, educators can become change agents and shift the historic oppressive narrative to create a system of empowerment as these individuals transition from transitional kindergarten to age 21 special education programs (TK-21) schools into adulthood.

Details

Contextualizing Critical Race Theory on Inclusive Education From a Scholar-Practitioner Perspective
Type: Book
ISBN: 978-1-80455-530-9

Keywords

Article
Publication date: 26 December 2023

Baburhan Uzum, Bedrettin Yazan, Sedat Akayoglu and Ufuk Keles

This study aims to examine how teacher candidates (TCs) in Türkiye and the USA navigate their intercultural communication skills in a telecollaboration project.

Abstract

Purpose

This study aims to examine how teacher candidates (TCs) in Türkiye and the USA navigate their intercultural communication skills in a telecollaboration project.

Design/methodology/approach

Forty-eight TCs participated (26 in Türkiye and 22 in the USA) in the study. TCs discussed critical issues in multicultural education on an online learning platform for six weeks. Their discussions were analyzed using content and discourse analysis.

Findings

The findings indicated that TCs approached the telecollaborative space as a translingual contact zone and positioned themselves and their interlocutors in the discourse by using the personal pronouns; I, we, you and they. When they positioned themselves using we (people in Türkiye/USA), they spoke on behalf of everyone included in the scope of we. Their interlocutors responded to these positionings either by accepting this positioning and responding with a parallel positioning or by engaging in translingual negotiation strategies to revise the scope of we and sharing some differences/nuances in beliefs and practices in their community.

Research limitations/implications

When TCs talk about their culture and community in a singular manner using we, they frame them as the same across every member in that community. When they ask questions to each other using you, the framing of the questions prime the respondents to sometimes relay their own specific experiences as the norm or consider experiences from different points of view through translingual negotiation strategies. A singular approach to culture(s) may affect the marginalized communities the most because they are lost in this representation, and their experiences and voices are not integrated in the narratives or integrated with stereotypical representation.

Practical implications

Teachers and teacher educators should first pay attention to their language choices, especially use of pronouns, which may communicate inclusion or exclusion in intercultural conversations. Next, they should prepare their students to adopt and practice language choices that communicate respect for cultural diversity and are inclusive of marginalized populations.

Social implications

Speakers’ pronoun use includes identity construction in discourse by drawing borders around and between communities and cultures with generalization and particularity, and by patrolling those borders to decide who is included and excluded. As a response, interlocutors use pronouns either to acknowledge those borders and respond with corresponding ones from their own context or negotiate alternative representations or further investigate for particularity or complexity. In short, pronouns could lead the direction of intercultural conversations toward criticality and complexity or otherwise, and might be reasons where there are breakdowns in communication or to fix those breakdowns.

Originality/value

This study shows that translingual negotiation strategies have explanatory power to examine how speakers from different language backgrounds negotiate second and third order positionings in the telecollaborative space.

Details

Journal for Multicultural Education, vol. 18 no. 1/2
Type: Research Article
ISSN: 2053-535X

Keywords

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