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1 – 10 of over 1000
Article
Publication date: 2 April 2024

Chenyu Zhang, Hongtao Xu and Yaodong Da

Thermal protection of a flange is critical for preventing tower icing and collapse of wind turbines (WTs) in extremely cold weather. This study aims to develop a novel thermal…

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Abstract

Purpose

Thermal protection of a flange is critical for preventing tower icing and collapse of wind turbines (WTs) in extremely cold weather. This study aims to develop a novel thermal protection system for the WTs flanges using an electrical heat-tracing element.

Design/methodology/approach

A three-dimensional model and the Poly-Hexacore mesh structure are used, and the fluid-solid coupling method was validated and then deployed to analyze the heat transfer and convection process. Intra-volumetric heat sources are applied to represent the heat generated by the heating element, and the dynamic boundary conditions are considered. The steady temperature and temperature uniformity of the flange are the assessment criteria for the thermal protection performance of the heating element.

Findings

Enlarging the heating area and increasing the heating power improved the flange's temperature and temperature uniformity. A heating power of 4.9 kW was suitable for engineering applications with the lowest temperature nonuniformity. Compared with continuous heating, the increased temperature nonuniformity was buffered, and the electrical power consumption was reduced by half using pulse heating. Pulse heating time intervals of 1, 3 and 4 h were determined for the spring, autumn and winter, respectively.

Originality/value

The originality of this study is to propose a novel electrical heat-tracing thermal protection system for the WTs flanges. The effect of different arrangements, heating powers and heating strategies was studied, by which the theoretical basis is provided for a stable and long-term utilization of the WT flange.

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: 29 December 2023

Jyoti Ranjan Mohapatra and Manoj Kumar Moharana

This study aims to investigate a new circuitous minichannel cold plate (MCP) design involving flow fragmentation. The overall thermal performance and the temperature uniformity…

Abstract

Purpose

This study aims to investigate a new circuitous minichannel cold plate (MCP) design involving flow fragmentation. The overall thermal performance and the temperature uniformity analysis are performed and compared with the traditional serpentine design. The substrate thickness and its thermal conductivity are varied to analyse the effect of axial-back conduction due to the conjugate nature of heat transfer.

Design/methodology/approach

The traditional serpentine minichannel is modified into five new fragmented designs with two inlets and two outlets. A three-dimensional numerical model involving the effect of conjugate heat transfer with a single-phase laminar fluid flow subjected to constant heat flux is solved using a finite volume-based computational fluid dynamics solver.

Findings

The minimum and maximum temperature differences are observed for the two branch fragmented flow designs. The two-branch and middle channel fragmented design shows better temperature uniformity over other designs while the three-branch fragmented designs exhibited better hydrodynamic performance.

Practical implications

MCPs could be used as an indirect liquid cooling method for battery thermal management of pouch and prismatic cells. Coupling the modified cold plates with a battery module and investigating the effect of different battery parameters and environmental effects in a transient state are the prospects for further research.

Originality/value

The study involves several aspects of evaluation for a conclusive decision on optimum channel design by analysing the performance plot between the temperature uniformity index, average base temperature and overall thermal performance. The new fragmented channels are designed in a way to facilitate the fluid towards the outlet in the minimum possible path thereby reducing the pressure drop, also maximizing the heat transfer and temperature uniformity from the substrate due to two inlets and a reversed-flow pattern. Simplified minichannel designs are proposed in this study for practical deployment and ease of manufacturability.

Details

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

Keywords

Article
Publication date: 26 September 2022

Gustavo Morales-Alonso, José Antonio Blanco-Serrano, Yilsy Núñez Guerrero, Mercedes Grijalvo and Francisco José Blanco Jimenez

This research aims at the theory of planned behavior (TPB) and the global entrepreneurship monitor (GEM) framework – How can cognitive traits for entrepreneurship be used by…

Abstract

Purpose

This research aims at the theory of planned behavior (TPB) and the global entrepreneurship monitor (GEM) framework – How can cognitive traits for entrepreneurship be used by incubators and accelerators?

Design/methodology/approach

In this research the authors analyze the factors that catalyze the founding of new technology-based firms. From a practitioner stand-point, the GEM posits that these factors can be classified as contextual, social and individual factors. The present study focuses on the latter, looking into how demographic characteristics, possession of human capital and cognitive traits interrelate. The authors rely on a sample of 141 technological new ventures being incubated in Madrid, Spain, which is analyzed with the multilayer perceptron technique.

Findings

The results show that cognitive traits, as defined in the TPB, act as the “last mile” in the entrepreneurial decision process, while demographic and human capital factors appear to antecede them. These results are relevant for incubators and accelerators, which now gain a better, more complete understanding of success factors of their incubatees.

Originality/value

This research deals both with practitioners' view of entrepreneurship and with scientific literature, intertwining both with the purpose of providing valuable information for incubators and accelerators.

Open Access
Article
Publication date: 28 February 2024

Ilkka Tapani Ojansivu

This study aims to focus on a specific project marketing concept, i.e. “discontinuity,” and analyzes how this concept emerged in project marketing, becoming its key scholarly…

Abstract

Purpose

This study aims to focus on a specific project marketing concept, i.e. “discontinuity,” and analyzes how this concept emerged in project marketing, becoming its key scholarly embodiment, how it became decoupled from the increasingly service-intensive project business practice and what the relevance of discontinuity is for project marketers moving forward.

Design/methodology/approach

This study is built on a systematic literature review of 31 years (1993–2023) of publishing data from major marketing and management journals.

Findings

This study provides three findings. First, the author reveals the risks related to marketing scholars and practitioners losing sight of each other as business practices evolve much faster than scholarly research can keep up. Second, the author highlights the role of interdisciplinary collaboration in advancing conceptual innovations. Finally, the research elucidates the need for broader metatheoretical reflection to keep this research tradition on an upward trajectory.

Research limitations/implications

The aim of this study is not to criticize project marketing, as many strands of business-to-business (B2B) marketing face the same challenge, but to elucidate a need for conceptual innovations, collaboration with practitioners and other disciplines and broader metatheoretical reflection to keep this research tradition on an upward trajectory.

Originality/value

This study makes several contributions to the project marketing research tradition. First, it reviews the emergence and dissipation of the concept of discontinuity, drawing on semantical, etymological and epistemological insights. It also reflects on recent disruptions in the marketplace and envisions future research trajectories for this elusive concept. In addition, the author develops a conceptual framework that combines project types with exchange elements in project and service businesses. This conceptual framework helps elucidate what part of the exchange is continuing and what is discontinuing in the resulting business relationships. Furthermore, the research contributes to B2B marketing more broadly by highlighting the fleeting correspondence between theory and the real world. It underscores the need for constant updates to maintain relevance.

Details

Journal of Business & Industrial Marketing, vol. 39 no. 3
Type: Research Article
ISSN: 0885-8624

Keywords

Open Access
Article
Publication date: 16 April 2024

Isabella Melissa Gebert and Felipa de Mello-Sampayo

This study aims to assess the efficiency of Brazil, Russia, India, China, South Africa (BRICS) countries in achieving sustainable development by analyzing their ability to convert…

Abstract

Purpose

This study aims to assess the efficiency of Brazil, Russia, India, China, South Africa (BRICS) countries in achieving sustainable development by analyzing their ability to convert resources and technological innovations into sustainable outcomes.

Design/methodology/approach

Using data envelopment analysis (DEA), the study evaluates the economic, environmental and social efficiency of BRICS countries over the period 2010–2018. It ranks these countries based on their sustainable development performance and compares them to the period 2000–2007.

Findings

The study reveals varied efficiency levels among BRICS countries. Russia and South Africa lead in certain sustainable development aspects. South Africa excels in environmental sustainability, whereas Brazil is efficient in resource utilization for sustainable growth. China and India, despite economic growth, face challenges such as pollution and lower quality of life.

Research limitations/implications

The study’s findings are constrained by the DEA methodology and the selection of variables. It highlights the need for more nuanced research incorporating recent global events such as the COVID-19 pandemic and geopolitical shifts.

Practical implications

Insights from this study can inform targeted and effective sustainability strategies in BRICS nations, focusing on areas such as industrial quality improvement, employment conditions and environmental policies.

Social implications

The study underscores the importance of balancing economic growth with social and environmental considerations, highlighting the need for policies addressing inequality, poverty and environmental degradation.

Originality/value

This research provides a unique comparative analysis of BRICS countries’ sustainable development efficiency, challenging conventional perceptions and offering a new perspective on their progress.

Details

International Journal of Development Issues, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1446-8956

Keywords

Article
Publication date: 2 April 2024

Minyan Wei, Juntao Zheng, Shouzhen Zeng and Yun Jin

The main aim of this paper is to establish a reasonable and scientific evaluation index system to assess the high quality and full employment (HQaFE).

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Abstract

Purpose

The main aim of this paper is to establish a reasonable and scientific evaluation index system to assess the high quality and full employment (HQaFE).

Design/methodology/approach

This paper uses a novel Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) multi-criteria framework to evaluate the quality and quantity of employment, wherein the integrated weights of attributes are determined by the combined the Criteria Importance Through Inter-criteria Correlation (CRITIC) and entropy approaches.

Findings

Firstly, the gap in the Yangtze River Delta in employment quality is narrowing year by year; secondly, employment skills as well as employment supply and demand are the primary indicators that determine the HQaFE; finally, the evaluation scores are clearly hierarchical, in the order of Shanghai, Jiangsu, Zhejiang and Anhui.

Originality/value

A scientific and reasonable evaluation index system is constructed. A novel CRITIC-entropy-TOPSIS evaluation is proposed to make the results more objective. Some policy recommendations that can promote the achievement of HQaFE are proposed.

Details

International Journal of Intelligent Computing and Cybernetics, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1756-378X

Keywords

Open Access
Article
Publication date: 23 January 2024

Rubens C.N. Oliveira and Zhipeng Zhang

The purpose of this study is to address the extended travel time caused by dwelling time at stations for passengers on traditional rail transit lines. To mitigate this issue, the…

Abstract

Purpose

The purpose of this study is to address the extended travel time caused by dwelling time at stations for passengers on traditional rail transit lines. To mitigate this issue, the authors propose the “Non-stop” design, which involves trains comprised of modular vehicles that can couple and uncouple from each other during operation, thereby eliminating dwelling time at stations..

Design/methodology/approach

The main contributions of this paper are threefold: first, to introduce the concept of non-stop rail transit lines, which, to the best of the authors’ knowledge, has not been researched in the literature; second, to develop a framework for the operation schedule of such a line; and third, the author evaluate the potential of its implementation in terms of total passenger travel time.

Findings

The total travel time was reduced by 6% to 32.91%. The results show that the savings were more significant for long commutes and low train occupancy rates.

Research limitations/implications

The non-stop system can improve existing lines without the need for the construction of additional facilities, but it requires technological advances for rolling stock.

Originality/value

To eliminate dwelling time at stations, the authors present the “Non-stop” design, which is based on trains composed of locomotives that couple and uncouple from each other during operation, which to the best of the authors’ knowledge has not been researched in the literature.

Details

Smart and Resilient Transportation, vol. 6 no. 1
Type: Research Article
ISSN: 2632-0487

Keywords

Article
Publication date: 27 February 2024

Hasan Evrim Arici, Mehmet Ali Köseoglu, Cagdas Aydin, Ceren Aydin and Levent Altinay

This study aims to identify the role of innovation research in formulating the intellectual structure of the hospitality and tourism literature by performing a bibliometric…

Abstract

Purpose

This study aims to identify the role of innovation research in formulating the intellectual structure of the hospitality and tourism literature by performing a bibliometric analysis.

Design/methodology/approach

In total, 6,255 journal articles on innovation were gathered from Scopus and analyzed using co-citation, bibliographic coupling and thematic content analyses. The most influential articles were also carefully read to reveal a nomological network of innovation research in hospitality and tourism scholarship.

Findings

Co-citation analysis reveals that there are six significant clusters in the field of innovation research. Various philosophical underpinnings might be used in different circumstances, with actor-network and Schumpeterian theory playing significant roles. A review of current works using bibliographic coupling reveals five interesting emerging research areas and makes numerous recommendations for when to conduct more studies. A review of influential articles displayed differences between the co-citation and bibliographic coupling analysis findings and produced a framework for further investigation of the knowledge field.

Originality/value

This paper is among the first integrative reviews on innovation research in hospitality and tourism by quantitatively reviewing published articles and qualitatively reviewing the content of the most influential studies.

Details

Journal of Hospitality and Tourism Technology, vol. 15 no. 2
Type: Research Article
ISSN: 1757-9880

Keywords

Article
Publication date: 17 April 2024

Bingwei Gao, Hongjian Zhao, Wenlong Han and Shilong Xue

This study proposes a predictive neural network model reference decoupling control method for the coupling problem between the leg joints of hydraulic quadruped robots, and…

Abstract

Purpose

This study proposes a predictive neural network model reference decoupling control method for the coupling problem between the leg joints of hydraulic quadruped robots, and verifies its decoupling effect..

Design/methodology/approach

The machine–hydraulic cross-linking coupling is studied as the coupling behavior of the hydraulically driven quadruped robot, and the mechanical dynamics coupling force of the robot system is controlled as the disturbance force of the hydraulic system through the Jacobian matrix transformation. According to the principle of multivariable decoupling, a prediction-based neural network model reference decoupling control method is proposed; each module of the control algorithm is designed one by one, and the stability of the system is analyzed by the Lyapunov stability theorem.

Findings

The simulation and experimental research on the robot joint decoupling control method is carried out, and the prediction-based neural network model reference decoupling control method is compared with the decoupling control method without any decoupling control method. The results show that taking the coupling effect experiment between the hip joint and knee joint as an example, after using the predictive neural network model reference decoupling control method, the phase lag of the hip joint response line was reduced from 20.3° to 14.8°, the amplitude attenuation was reduced from 1.82% to 0.21%, the maximum error of the knee joint coupling line was reduced from 0.67 mm to 0.16 mm and the coupling effect between the hip joint and knee joint was reduced from 1.9% to 0.48%, achieving good decoupling.

Originality/value

The prediction-based neural network model reference decoupling control method proposed in this paper can use the neural network model to predict the next output of the system according to the input and output. Finally, the weights of the neural network are corrected online according to the predicted output and the given reference output, so that the optimization index of the neural network decoupling controller is extremely small, and the purpose of decoupling control is achieved.

Details

Robotic Intelligence and Automation, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2754-6969

Keywords

Article
Publication date: 10 November 2022

Xinxing Yin, Juan Chen, Wenxin Yu, Yuan Huang, Wenxiang Wei, Xinjie Xiang and Hao Yan

This study aims to improve the complexity of chaotic systems and the security accuracy of information encrypted transmission. Applying five-dimensional memristive Hopfield neural…

Abstract

Purpose

This study aims to improve the complexity of chaotic systems and the security accuracy of information encrypted transmission. Applying five-dimensional memristive Hopfield neural network (5D-HNN) to secure communication will greatly improve the confidentiality of signal transmission and greatly enhance the anticracking ability of the system.

Design/methodology/approach

Chaos masking: Chaos masking is the process of superimposing a message signal directly into a chaotic signal and masking the signal using the randomness of the chaotic output. Synchronous coupling: The coupled synchronization method first replicates the drive system to get the response system, and then adds the appropriate coupling term between the drive The synchronization error and the coupling term of the system will eventually converge to zero with time. The synchronization error and coupling term of the system will eventually converge to zero over time.

Findings

A 5D memristive neural network is obtained based on the original four-dimensional memristive neural network through the feedback control method. The system has five equations and contains infinite balance points. Compared with other systems, the 5D-HNN has rich dynamic behaviors, and the most unique feature is that it has multistable characteristics. First, its dissipation property, equilibrium point stability, bifurcation graph and Lyapunov exponent spectrum are analyzed to verify its chaotic state, and the system characteristics are more complex. Different dynamic characteristics can be obtained by adjusting the parameter k.

Originality/value

A new 5D memristive HNN is proposed and used in the secure communication

Details

Circuit World, vol. 50 no. 1
Type: Research Article
ISSN: 0305-6120

Keywords

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