Search results

The purpose of this paper is to perform the simulation to explore the gap flow field under a hypersonic air flow. Thermal protection systems of hypersonic vehicles generally consist of thermal insulation tiles, and gaps between these tiles probably cause a severe local aerodynamic thermal effect.

The discretizations of convection flux term and temporal term in the governing equation with chemical equilibrium, respectively, take AUSM+-up flux-vector splitting scheme and the implicit lower-upper symmetric Gauss–Seidel method. Based on these, the flow field in a deep gap is simulated by means of the computer codes that the authors have written.

The numerical results show that the heat flux distribution in a gap has a good agreement with experimental results. Importantly, the distribution of heat flux is “U” shaped and the maximum of the heat flux occurs at the windward corner of a gap.

To explore the gap flow field under a hypersonic air flow, which is a chemically reacting, all speed and viscous flow, a novel model with an equivalent ratio of specific heats is presented. The investigation in this paper has a guide for the design of the thermal protection system in hypersonic vehicles.

The purpose of this paper is to develop a method for the existence, uniqueness and globally robust stability of the equilibrium point for Cohen–Grossberg neural networks with time-varying delays, continuous distributed delays and a kind of discontinuous activation functions.

Based on the Leray–Schauder alternative theorem and chain rule, by using a novel integral inequality dealing with monotone non-decreasing function, the authors obtain a delay-dependent sufficient condition with less conservativeness for robust stability of considered neural networks.

It turns out that the authors’ delay-dependent sufficient condition can be formed in terms of linear matrix inequalities conditions. Two examples show the effectiveness of the obtained results.

The novelty of the proposed approach lies in dealing with a new kind of discontinuous activation functions by using the Leray–Schauder alternative theorem, chain rule and a novel integral inequality on monotone non-decreasing function.

The study aims to analyse international studies on the impact that new forms of control and performativity in higher education have on academics’ identity. The aim was threefold, namely, to provide an overview of the main published findings; to establish biases and future lines of research and to offer a starting point to stimulate a debate on the future of universities.

The present study consists of a systematic review aimed at providing an overview of the main professional identities (PIs) described in the literature in the past 10 years. A bibliographic search was conducted on the Web of Science, SCOPUS and Education Resources Information Centre, which yielded a total of 26 articles that were subsequently subjected to thematic analysis.

The study provides an overview of the types of identities developed by academics as a result of the new forms of control. Among the main findings, this study reveals a clear predominance of PIs characterised by submission to the new neoliberal demands. The professional, social and health consequences associated with these identities are also highlighted. Finally, a proposal is made for future research to better understand how these new PIs are constructed and developed.

Because of the chosen filters or databases, the study could have omitted possible articles relevant to this review. Therefore, researchers are encouraged to replicate such a study by expanding, for example, the languages used.

This study helps us to obtain a detailed description of the different identities generated as a consequence of the new governance of higher education. Furthermore, possible implications for mitigating this situation are mentioned.

Introduction: As the human population grows, consumer demand for digital services tailored to their specific needs also increases. To improve the financial performance of farms and meet the need for food of a growing population, farmers and agribusinesses have started incorporating distributed ledger technology into agricultural and farm management software. These developments in the agriculture sector may lead to realising sustainable development goals.

Purpose: Several researchers have done studies to explore the features and benefits of blockchain technology in the field of agriculture. There is a need to analyse the available literature to identify the use of this technology in agriculture and the scope of further research. This chapter will mainly focus on its publication trend, journal productivity and impact, prolific studies, and coherent themes.

Methodology: For a comprehensive review, bibliometric and content analysis of 71 open-access articles collected through a structured database of Mendeley is done. These articles were published during 2017–2021.

Findings: The execution of blockchain is continuously increasing in the agriculture sector, which has resulted in automation in supply chain management, land registrations, and crop insurance. The study revolves around supply chain management, digitisation of agriculture, and sustainable economic development. This study’s conclusions can help agriculturalists improve their understanding of blockchain implementation in agriculture. The study also gives directions for future research.

Currently heating and cooling in buildings is responsible for over 30% of the primary energy consumption in the United Kingdom with a similar amount in China. We analyze heat pumps and district thermal energy network for efficient buildings. Their advantages are examined (i.e., flexibility in choosing heat sources, reduction of fuel consumption and increased environmental quality, enhanced community energy management, reduced costs for end users) together with their drawbacks, when they are intended as means for efficient building heating and cooling.

A literature review observed a range of operating conditions and challenges associated with the efficient operation of district heating and cooling networks, comparing primarily the UK’s and China’s experiences, but also acknowledging the areas of expertise of European, the United States, and Japan. It was noted that the efficiency of cooling networks is still in its infancy but heating networks could benefit from lower distribution temperatures to reduce thermal losses. Such temperatures are suitable for space heating methods provided by, for example, underfloor heating, enhanced area hydronic radiators, or fan-assisted hydronic radiators. However, to use existing higher temperature hydronic radiator systems (typically at a temperatures of >70°C) a modified heat pump was proposed, tested, and evaluated in an administrative building. The results appears to be very successful.

District heating is a proven energy-efficient mechanism for delivering space heating. They can also be adaptable for space cooling applications with either parallel heating and cooling circuits or in regions of well-defined seasons, on flow and return circuit with a defined change-over period from heating to cooling. Renewable energy sources can provide either heating or cooling through, for example, biomass boilers, photovoltaics, solar thermal, etc. However, for lower loss district heating systems, lower distribution temperatures are required. Advanced heat pumps can efficiently bridge the gap between lower temperature distribution systems and buildings with higher temperature hydronic heating systems

This chapter presents a case for district heating (and cooling). It demonstrates the benefits of reduced temperatures in district heating networks to reduce losses but also illustrates the need for temperature upgrading where building heating systems require higher temperatures. Thus, a novel heat pump was developed and successfully tested.

WeChat official account (WCOA) is an emerging and important platform for academic library services, which greatly accelerates the development of this field. This article aims to identify key evaluation indicators for users' satisfaction of the Academic Library WeChat Official Account (ALWCOA) as a reference for future improvements.

Based on the updated DeLone and McLean (D&M)’s model and Delphi method, an evaluation system of ALWCOA satisfaction was constructed. Then 212 university students were recruited to fill out a questionnaire on evaluation indicators. The grey relational analysis (GRA) and Pareto's principle were employed to analyze the questionnaire and select key evaluation indicators.

An ALWCOA service satisfaction evaluation system with three evaluation dimensions and 15 evaluation indicators was constructed, and three key evaluation indicators were identified, including service responsiveness, information timeliness and system security.

This article provides a strategy for assessing ALWCOA service satisfaction, as well as insights for improving of ALWCOA service. Specifically, academic libraries should pay more attention to improving service responsiveness, information timeliness and system security.

This article innovatively applied the updated D&M model in academic library service. Additionally, it facilitates the development of research fields, such as academic library services, microservices and user service evaluation, and provides a case study to better understand the WCOA.

The notion of sustainability broadly builds upon the development of the present without hampering the needs of the future generation. Accordingly, the contemporary development programmes, in general, emphasise on minimising the adverse bearings of climate change and arresting the irreversible ecological degradation following the implementation of the growth-oriented economic models. While such idea of sustainable development is expected to be applied across different sectors, the traditional urban development projects such as the Integrated Development of Small and Medium Towns (IDSMT) (1979), the Mega-City Scheme (1993), and the Jawaharlal Nehru National Urban Renewal Mission (JNNURM) (2005) focussed mainly on physical infrastructure with inadequate emphasis on the ecological aspects and sustainability. However, with the experiences of globalisation and the negative impact of changing climate, the recent urban development initiatives across the world have gone through considerable redesigning, and the idea of eco-city, compact city, sustainable city, etc., have taken the central place in the project proposals. In this connection, the Smart City Mission (SCM) (2015) of the Government of India has emerged as an important initiative to facilitate improvement in the standard of living along with economic growth through the development of urban infrastructure and integration with intelligent technologies. This chapter attempts to understand how the projects under the SCM have incorporated various ecological aspects to transform the cities into liveable and sustainable ones for the future generation. Using secondary data and carrying out a comparative analysis of selected smart city proposals, this chapter finds that there is still a lack of adequate emphasis on ecological sustainability in many smart city proposals. This chapter suggests revisiting the smart city proposals, and initiatives should be made towards the development of urban areas in a sustainable way.

Introduction: Studies on the insurance sector/companies have, in recent years, taken their place in literature at an increasing rate. Especially after the 2008 global financial crisis, the need for people to ensure their assets has structurally changed both the transaction volume and the yield structure of insurance sector. The increase in demand for insurance has also increased the appetite of investors to make an investment on this sector. The transaction volume of the insurance sector has increased year by year coupled with the number of insurance companies traded on the stock exchanges has started to increase in the same direction.

Aim: This chapter aims to determine the return structure of the Borsa Istanbul Insurance Index (XSGRT) based on daily closing values.

Method: Markedly with similar studies in the literature review, the authors determined that the Markov Regime Switching (MRS) model is the best-suited model for the current research. It was applied for the data set of XSGRT Index from 1997 to 2020.

Results: The result shows that XSGRT has three regimes named as expansion regime, normal regime and recession regime. Subsequently, it has been determined that the index generally attends to transition from the recession regime to the expansion regime and normal regime. This outcome is statistically significant at a 5% significance level and confirmed by backtesting results. Likewise, the duration of the recession regime is longer than the normal and expansion regime.

Conclusion: Despite the fact that the XSGRT has not yet completed its development compared to other main and sectoral indices, it is one of the indices that offer attractive earnings for investors. To put it differently, the desire of insurance companies to stay longer totally in the normal and expansion period and their immediate exit from the recession period provides them with a significant competitive advantage in contrast to other indices.

Originality/Value: This research contributes to the literature by providing additional evidence for existing studies using the longer duration of data set and applying the MRS model for Insurance Index. Best of our knowledge, it is the first study that examines the return structure of XSGRT based on its daily closing values from 1997 to 2020. In essence, investors can use the result of this study and compare it with other stock indices to make the accurate investment decision to maximise their welfare and return on their equity investments. The authors suggest that not only the return but also the regime structures of the invested shares (indices) should be taken into account for investment decisions.

This paper assesses to what extent the workplace union power has been built under the Professional Union Leader and Organizer Program (PULOP) in China in the local community-based private workplaces. Data obtained from in-depth interviews with union leaders, rank-and-file members, and data from documentary sources are deployed. Findings show that, for the purpose of stabilizing labor-management relations in these community-based workplaces, the PULOP attempts to reinforce implementation of existing labor law and regulations regarding wages and working conditions by organizing community-based private employers. However, without workers’ support from the bottom up, the power of the newly established workplace union associations are rather precarious. The PULOP union leaders are still distant to the organized workplaces and to the workers at these workplaces; and the organized employers are still reluctant or even hostile towards PULOP activities. The paper, therefore, concludes by drawing out the implications of the finding that, without genuine worker participation in union formation and operation processes, the administrative power held by the union bureaucracies cannot be effectively translated into workplace union power via the PULOP initiative.

Blockchain technology was once only associated with the financial industry, but it is now being used in a variety of industries, including education. Researchers all over the world take a keen interest in studying the various applications of blockchain technology for the last 4–5 years. The current study is a review of previously published studies on blockchain technology’s applicability in the sector of education. The systematic review was used to conduct the qualitative analysis using the PRISMA Framework (Preferred Reporting Items for Systematic Review and Meta-Analysis). For this comprehensive literature review analysis, 99 publications were chosen in the final stage of selection. Bibliometric analysis is employed to analyse the collected data. Authorship analysis, co-authorship analysis, keyword co-occurrences, and important applications of blockchain in education are the primary parts in which the literature’s findings are organised. Important directions are given for researchers and academicians involved in blockchain-related research who may use the bibliometric analysis of the present study as a reference.