Search results

1 – 10 of 10
Article
Publication date: 17 September 2024

Wanfeng Zhu, Petia Venkova Sice, Wenchun Zhang, Krystyna Krajewska and Zhangyang Zhao

The purpose of this paper is to bring into the public domain converging ways of thinking about reality and human systems, exploring parallels between the theory of Physical Vacuum…

Abstract

Purpose

The purpose of this paper is to bring into the public domain converging ways of thinking about reality and human systems, exploring parallels between the theory of Physical Vacuum and the concept of Qi in Medical Qigong science.

Design/methodology/approach

The approach adopted in this paper includes: review of the relevant literature; dialogues between the first two authors over an eight-month period; review of the findings and discussion of interpretations by all.

Findings

There is evidence for the existence of an ideal information field. This field is a real space-time torsion structure. Qi is a torsion field. It spreads with superluminal velocity and connects the whole Universe. Any entity is in a constant dynamic connection with everything else in the Universe.

Research limitations/implications

This paper offers limited discussion of the wider area of scientific discoveries.

Social implications

The findings may impact future interdisciplinary research, health/well-being practices and public policy.

Originality/value

There is no known to us publication interpreting the parallels between the theory of the Physical Vacuum and the concept of Qi.

Details

Kybernetes, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0368-492X

Keywords

Article
Publication date: 12 September 2024

Khairunnahar Suchana and Md. Mamun Molla

The present numerical investigation examines the magnetohydrodynamic (MHD) double diffusion natural convection of power-law non-Newtonian nano-encapsulated phase change materials…

Abstract

Purpose

The present numerical investigation examines the magnetohydrodynamic (MHD) double diffusion natural convection of power-law non-Newtonian nano-encapsulated phase change materials (NEPCMs) in a trapezoidal cavity.

Design/methodology/approach

The governing Navier-Stokes, energy and concentration equations based on the Cartesian curvilinear coordinates are solved using the collocated grid arrangement’s finite volume method. The in-house FORTRAN code is validated with the different benchmark problems. The NEPCM nanoparticles consist of a core-shell structure with Phase Change Material (PCM) at the core. The enclosure, shaped as a trapezoidal hollow, features a warmed (Th) left wall and a cold (Tc) right wall. Various parameters are considered, including the power law index (0.6 ≤ n ≤ 1.4), Hartmann number (0 ≤ Ha ≤ 30), Rayleigh number (104Ra ≤ 105) and fixed variables such as buoyancy ratio (Br = 0.8), Prandtl number (Pr = 6.2), Lewis number (Le = 5), fusion temperature (Θf = 0.5) and volume fraction (ϕ = 0.04).

Findings

The findings indicate a decrease in local Nusselt (Nu) and Sherwood (Sh) numbers with increasing Hartmann numbers (Ha). Additionally, for a shear-thinning fluid (n = 0.6) results in the maximum local Nu and Sh values. As the Rayleigh number (Ra) increases from 104 to 105, the structured vortex in the streamline pattern is disturbed. Furthermore, for different Ra values, an increase in n from 0.6 to 1.4 leads to a 67.43% to 76.88% decrease in average Nu and a 70% to 77% decrease in average Sh.

Research limitations/implications

This research is for two-dimensioal laminar flow only.

Practical implications

PCMs represent a class of practical substances that behave as a function of temperature and have the innate ability to absorb, release and store heated energy in the form of hidden fusion enthalpy, or heat. They are valuable in these systems as they can store significant energy at a relatively constant temperature through their latent heat phase change.

Originality/value

As per the literature review and the authors’ understanding, an examination has never been conducted on MHD double diffusion natural convection of power-law non-Newtonian NEPCMs within a trapezoidal enclosure. The current work is innovative since it combines NEPCMs with the effect of magnetic field Double diffusion Natural Convection of power-law non-Newtonian NEPCMs in a Trapezoidal enclosure. This outcome can be used to improve thermal management in energy storage systems, increasing safety and effectiveness.

Details

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

Keywords

Article
Publication date: 22 August 2024

Sandipan Kumar Das

The boundary integral method (BIM) is very attractive to practicing engineers as it reduces the dimensionality of the problem by one, thereby making the procedure computationally…

Abstract

Purpose

The boundary integral method (BIM) is very attractive to practicing engineers as it reduces the dimensionality of the problem by one, thereby making the procedure computationally inexpensive compared to its peers. The principal feature of this technique is the limitation of all its computations to only the boundaries of the domain. Although the procedure is well developed for the Laplace equation, the Poisson equation offers some computational challenges. Nevertheless, the literature provides a couple of solution methods. This paper revisits an alternate approach that has not gained much traction within the community. The purpose of this paper is to address the main bottleneck of that approach in an effort to popularize it and critically evaluate the errors introduced into the solution by that method.

Design/methodology/approach

The primary intent in the paper is to work on the particular solution of the Poisson equation by representing the source term through a Fourier series. The evaluation of the Fourier coefficients requires a rectangular domain even though the original domain can be of any arbitrary shape. The boundary conditions for the homogeneous solution gets modified by the projection of the particular solution on the original boundaries. The paper also develops a new Gauss quadrature procedure to compute the integrals appearing in the Fourier coefficients in case they cannot be analytically evaluated.

Findings

The current endeavor has developed two different representations of the source terms. A comprehensive set of benchmark exercises has successfully demonstrated the effectiveness of both the methods, especially the second one. A subsequent detailed analysis has identified the errors emanating from an inadequate number of boundary nodes and Fourier modes, a high difference in sizes between the particular solution and the original domains and the used Gauss quadrature integration procedures. Adequate mitigation procedures were successful in suppressing each of the above errors and in improving the solution accuracy to any desired level. A comparative study with the finite difference method revealed that the BIM was as accurate as the FDM but was computationally more efficient for problems of real-life scale. A later exercise minutely analyzed the heat transfer physics for a fin after validating the simulation results with the analytical solution that was separately derived. The final set of simulations demonstrated the applicability of the method to complicated geometries.

Originality/value

First, the newly developed Gauss quadrature integration procedure can efficiently compute the integrals during evaluation of the Fourier coefficients; the current literature lacks such a tool, thereby deterring researchers to adopt this category of methods. Second, to the best of the author’s knowledge, such a comprehensive error analysis of the solution method within the BIM framework for the Poisson equation does not currently exist in the literature. This particular exercise should go a long way in increasing the confidence of the research community to venture into this category of methods for the solution of the Poisson equation.

Details

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

Keywords

Article
Publication date: 9 July 2024

Xuehua Li and Lei Zhang

Lots of successful space missions require that the maneuvering spacecraft can reach the target spacecraft. Therefore, research on relative reachable domain (RRD) in target orbit…

Abstract

Purpose

Lots of successful space missions require that the maneuvering spacecraft can reach the target spacecraft. Therefore, research on relative reachable domain (RRD) in target orbit for maneuvering spacecraft is particularly important and is currently a hot-debated topic in the field of aerospace. This paper aims at analyzing and simulating the RRD in target orbit for maneuvering spacecrafts with a single fixed-magnitude impulse and continuous thrust, respectively, to provide a basis for analyzing the feasibility of spacecraft maneuvering missions and improving the design efficiency of spacecraft maneuvering missions.

Design/methodology/approach

Based on the kinematics model of relative motion, RRD in target orbit for maneuvering spacecraft with a single fixed-magnitude impulse can be calculated via analyzing the relationship between orbital elements, position vector and velocity vector of spacecrafts, and relevant studies are introduced to compare simulation results for the same case and validate the method proposed in the paper. With analysis of the dynamic model of relative motion, the calculation of RRD in target orbit for maneuvering spacecraft with continuous thrust can be transformed as the solution of the optimal control problem, and example emulations are carried out to validate the method.

Findings

For the case with a single fixed-magnitude impulse, simulation results show preliminarily that the method is in agreement with the method in Ref. (Wen et al., 2016), which treats the same case and thus is plausibly correct and feasible. For the case with continuous thrust, analysis and simulation results confirm the validity of the proposed method. The methods based on relative motion in this paper can efficiently determining the RRD in target orbit for maneuvering spacecraft.

Originality/value

Both theoretical analyses and simulation results indicate that the method proposed in this paper is comparatively simple but efficient for determine the RRD in target orbit for maneuvering spacecraft swiftly and precisely.

Details

Aircraft Engineering and Aerospace Technology, vol. 96 no. 6
Type: Research Article
ISSN: 1748-8842

Keywords

Book part
Publication date: 18 September 2024

Mohamad Syahrul Nizam Ibrahim, Shazali Johari, Amirah Sariyati Mohd Yahya, Rosmiza Mohd Zainol and Suziana Hassan

Gunung Mulu National Park (GMNP) is one of the two protected areas with UNESCO World Heritage Site (WHS) status in Malaysia. Until now, this area can only be accessed by tourists…

Abstract

Gunung Mulu National Park (GMNP) is one of the two protected areas with UNESCO World Heritage Site (WHS) status in Malaysia. Until now, this area can only be accessed by tourists via air and water transportation only. Recently, the government has proposed the construction of a road connecting GMNP to several areas, including Miri City through a high-impact infrastructure project. However, this project might instigate the potential benefits and challenges in terms of tourism development and community well-being. As custodians of the park, their support for this initiative needs to be dismantled so that the management of the national park can still be implemented holistically and does not jeopardise the current UNESCO status of WHS. WHS is UNESCO-designated area of cultural, historical, scientific, or other significant value, legally safeguarded by international agreements, and preserved for the benefit of future generations due to its exceptional value to humanity. Thus, this study aims to examine challenges and socioeconomic impacts of the proposed road among key informants' perspectives at Long Terawan Village, Long Iman Village, Batu Bungan Village and GMNP Headquarters. The study was conducted via in-depth interviews with 10 community members residing in the settlement, including a tribal chief, boatman, lodging operator, park guide and farmer, all of whom are professionals and representatives of the local community. They were designated as key informants on account of their extensive engagement and development within the community. Through a thematic analysis, their perspectives on the proposed roads to be built in the area were elucidated. The study offers pragmatic understanding of socioeconomic impact assessment, which could inform strategic decision-making by incorporating information regarding potential benefits and challenges of the proposed road construction to an isolated protected area.

Details

The Emerald Handbook of Tourism Economics and Sustainable Development
Type: Book
ISBN: 978-1-83753-709-9

Keywords

Abstract

Details

Recovering Women's Voices: Islam, Citizenship, and Patriarchy in Egypt
Type: Book
ISBN: 978-1-83608-249-1

Open Access
Book part
Publication date: 23 September 2024

Brayden G King

Organizations remain a vital sociological topic, but organizational sociology, as a subfield, has evolved significantly since its inception. In this paper, I argue that…

Abstract

Organizations remain a vital sociological topic, but organizational sociology, as a subfield, has evolved significantly since its inception. In this paper, I argue that organization sociology is becoming increasingly disconnected from organizational theory, as currently conceived. The focus of sociological research on organizations has become more empirically grounded in the study of social problems and how organizations contribute to them. Sociologists continue to see organizations as important actors in society that play a role in shaping social order and as contexts in which social processes play out. I propose two main sociological approaches for organizational research, which I describe as “organizations within society” and “society within organizations.” The first approach examines the role of organizations as building blocks of social structure and as social actors in their own right. The second approach treats organizations as platforms and locations of social interactions and the building of community. These approaches are somewhat disconnected from the sort of grand theorizing that characterizes much of organizational theory. I argue that the problem-oriented sociology of these two approaches offers a vital way for organizational scholars to expand and theoretically revitalize the field.

Details

Sociological Thinking in Contemporary Organizational Scholarship
Type: Book
ISBN: 978-1-83549-588-9

Keywords

Article
Publication date: 10 May 2022

Xuan Cu Le

Social media has progressively upgraded an interactive domain via online sociability and information-sharing. This study aims to formulate an information-sharing intention model…

Abstract

Purpose

Social media has progressively upgraded an interactive domain via online sociability and information-sharing. This study aims to formulate an information-sharing intention model by identifying the decisive role of intrinsic and extrinsic motivations.

Design/methodology/approach

Empirical data from 508 participants were collected to examine the structural model using structural equation modeling.

Findings

Results indicate that information-sharing intention is strongly promoted by intrinsic and extrinsic motivations. Furthermore, perceived herding, perceived crowd and intrinsic motivation boost substantially extrinsic motivation. Perceived herding is of utmost importance to extrinsic motivation, whereas emotional appeal and informative appeal are of paramount importance to intrinsic motivation. Moreover, source trust and exhibitionism are underlying motivations for intrinsic motivation.

Practical implications

The findings provide useful guidelines for practitioners to urge users into information-sharing via social media.

Originality/value

This study contributes significantly to the current literature by developing an effective mechanism of information-sharing through social media based on the motivational theory.

Details

VINE Journal of Information and Knowledge Management Systems, vol. 54 no. 5
Type: Research Article
ISSN: 2059-5891

Keywords

Content available
Article
Publication date: 9 September 2024

Siying Zhu and Cheng-Hsien Hsieh

Maritime transportation plays an important role in facilitating both the global and regional merchandise trade, where accurate trend prediction is crucial in assisting…

Abstract

Purpose

Maritime transportation plays an important role in facilitating both the global and regional merchandise trade, where accurate trend prediction is crucial in assisting decision-making in the industry. This paper aims to conduct a macro-level study to predict world vessel supply and demand.

Design/methodology/approach

The automatic autoregressive integrated moving average (ARIMA) is used for the univariate vessel supply and demand time-series forecasting based on the data records from 1980 to 2021.

Findings

For the future projection of the demand side, the predicted outcomes for total vessel demand and world dry cargo vessel demand until 2030 indicate upward trends. For the supply side, the predominant upward trends for world total vessel supply, oil tanker vessel supply, container vessel supply and other types of vessel supply are captured. The world bulk carrier vessel supply prediction results indicate an initial upward trend, followed by a slight decline, while the forecasted world general cargo vessel supply values remain relatively stable. By comparing the predicted percentage change rates, there is a gradual convergence between demand and supply change rates in the near future. We also find that the impact of the COVID-19 pandemic on the time-series prediction results is not statistically significant.

Originality/value

The results can provide policy implications in strategic planning and operation to various stakeholders in the shipping industry for vessel building, scrapping and deployment.

Details

Maritime Business Review, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2397-3757

Keywords

Open Access
Article
Publication date: 14 August 2024

Huijun Tu and Shitao Jin

Due to the complexity and diversity of megaprojects, the architectural programming process often involves multiple stakeholders, making decision-making difficult and susceptible…

Abstract

Purpose

Due to the complexity and diversity of megaprojects, the architectural programming process often involves multiple stakeholders, making decision-making difficult and susceptible to subjective factors. This study aims to propose an architectural programming methodology system (APMS) for megaprojects based on group decision-making model to enhance the accuracy and transparency of decision-making, and to facilitate participation and integration among stakeholders. This method allows multiple interest groups to participate in decision-making, gathers various perspectives and opinions, thereby improving the quality and efficiency of architectural programming and promoting the smooth implementation of projects.

Design/methodology/approach

This study first clarifies the decision-making subjects, decision objects, and decision methods of APMS based on group decision-making theory and value-based architectural programming methods. Furthermore, the entropy weight method and fuzzy TOPSIS method are employed as calculation methods to comprehensively evaluate decision alternatives and derive optimal decision conclusions. The workflow of APMS consists of four stages: preparation, information, decision, and evaluation, ensuring the scientific and systematic of the decision-making process.

Findings

This study conducted field research and empirical analysis on a practical megaproject of a comprehensive transport hub to verify the effectiveness of APMS. The results show that, in terms of both short-distance and long-distance transportation modes, the decision-making results of APMS are largely consistent with the preliminary programming outcomes of the project. However, regarding transfer modes, the APMS decision-making results revealed certain discrepancies between the project's current status and the preliminary programming.

Originality/value

APMS addresses the shortcomings in decision accuracy and stakeholder participation and integration in the current field of architectural programming. It not only enhances stakeholder participation and interaction but also considers various opinions and interests comprehensively. Additionally, APMS has significant potential in optimizing project performance, accelerating project processes, and reducing resource waste.

Details

Engineering, Construction and Architectural Management, vol. 31 no. 13
Type: Research Article
ISSN: 0969-9988

Keywords

1 – 10 of 10