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1 – 10 of over 2000Yong Li, Yingchun Zhang, Gongnan Xie and Bengt Ake Sunden
This paper aims to comprehensively clarify the research status of thermal transport of supercritical aviation kerosene, with particular interests in the effect of cracking on heat…
Abstract
Purpose
This paper aims to comprehensively clarify the research status of thermal transport of supercritical aviation kerosene, with particular interests in the effect of cracking on heat transfer.
Design/methodology/approach
A brief review of current research on supercritical aviation kerosene is presented in views of the surrogate model of hydrocarbon fuels, chemical cracking mechanism of hydrocarbon fuels, thermo-physical properties of hydrocarbon fuels, turbulence models, flow characteristics and thermal performances, which indicates that more efforts need to be directed into these topics. Therefore, supercritical thermal transport of n-decane is then computationally investigated in the condition of thermal pyrolysis, while the ASPEN HYSYS gives the properties of n-decane and pyrolysis products. In addition, the one-step chemical cracking mechanism and SST k-ω turbulence model are applied with relatively high precision.
Findings
The existing surrogate models of aviation kerosene are limited to a specific scope of application and their thermo-physical properties deviate from the experimental data. The turbulence models used to implement numerical simulation should be studied to further improve the prediction accuracy. The thermal-induced acceleration is driven by the drastic density change, which is caused by the production of small molecules. The wall temperature of the combustion chamber can be effectively reduced by this behavior, i.e. the phenomenon of heat transfer deterioration can be attenuated or suppressed by thermal pyrolysis.
Originality/value
The issues in numerical studies of supercritical aviation kerosene are clearly revealed, and the conjugation mechanism between thermal pyrolysis and convective heat transfer is initially presented.
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Prateek Kalia, Bhavana Behal, Kulvinder Kaur and Deepa Mehta
This exploratory study aims to discover the different forms of challenges encountered by school stakeholders, including students, teachers, parents and management due to the…
Abstract
Purpose
This exploratory study aims to discover the different forms of challenges encountered by school stakeholders, including students, teachers, parents and management due to the coronavirus disease 2019 (COVID-19) pandemic.
Design/methodology/approach
Qualitative methodology was deployed for the study. A purposive sampling technique was used to select the respondents for a semi-structured interview. Data were examined using interpretative phenomenological analysis (IPA).
Findings
It was found that each stakeholder faced four different challenges: mental distress, physical immobility, financial crunches and technological concerns. Findings suggest that teachers are experiencing higher financial, technological and physical challenges as compared to other stakeholders followed by parents.
Originality/value
This paper discusses the major challenges faced by each stakeholder along with the opportunities. These findings will be useful for educationists, regulatory authorities, policymakers and management of educational institutions in developing countries to revisit their policy frameworks to develop new strategies and processes for the smooth implementation of remote learning during a period of uncertainty.
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Christian Koranteng, Barbara Simons and Kwabena Abrokwa Gyimah
Given the climatic context and economic challenge of Ghana in its developmental strides, energy use of office buildings continues to be a task on the economy. Therefore, the study…
Abstract
Purpose
Given the climatic context and economic challenge of Ghana in its developmental strides, energy use of office buildings continues to be a task on the economy. Therefore, the study was about finding measures that could reduce cooling loads in 10 office buildings. The paper presents the outcome of a long-term study of the thermal conditions in a selected number of office buildings in Accra and Kumasi, Ghana.
Design/methodology/approach
Through long-term monitoring of environmental data, the buildings were consequently modelled in a simulation application. Thereafter, a validation of the simulation models (using regression coefficients, r2 of 0.53–0.90) was undertaken towards finding measures to reduce cooling loads.
Findings
The results showed various potentials of efficient lighting, thermal mass, night ventilation, insulation to attic floors, efficient glazing, blind deployments, etc. in reducing cooling loads in the range of 2–17.5%. By combining the potential measures to study their synergistic effects on the loads, 35, 39 and 38% improvements were achieved for the low-rise, multi-storey and fully glazed office buildings.
Originality/value
These potential measures ought to be incorporated in the design, specification, construction and operation of Ghanaian office buildings to reduce the burden on the economy and the environment. Now more than ever, there is the need for climatic regions to come up with empirical data that could help relieve the world's economies from the post-pandemic stress.
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Giulia Gastaldello, Nadia Streletskaya and Luca Rossetto
This study aims to provide a comprehensive overview on positive drivers and negative factors connected to the Covid-19 pandemic which can jointly shape wine tourism intentions.
Abstract
Purpose
This study aims to provide a comprehensive overview on positive drivers and negative factors connected to the Covid-19 pandemic which can jointly shape wine tourism intentions.
Design/methodology/approach
The present study relies on a large sample of 399 US wine tourists. Partial least square structural equation modelling is adopted for data analysis.
Findings
Results reveal that willingness to avoid Covid risk while travelling negatively impacts wine tourism intentions and competitively mediates the effect of Covid phobia. Both situational and personal involvement with wine are key antecedents of future wine tourism intentions.
Research limitations/implications
This research contributes to understand the role of willingness to avoid travel-related risks during health crises. Furthermore, it improves existing knowledge on the effect of wine involvement on wine tourism intentions, highlighting the predictive relevance of situational involvement in explaining this relationship.
Practical implications
Results constitute critical information to practitioners and destination management operators for improving their resilience under similar circumstances. Updated information on wine tourists’ profile is also provided.
Originality/value
To the best of the authors’ knowledge, this is among the first studies exploring how positive and negative drivers act synergically in affecting wine tourism intentions after the Covid-19 outbreak.
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Md Ozair Arshad, Shahbaz Khan, Abid Haleem, Hannan Mansoor, Md Osaid Arshad and Md Ekrama Arshad
Covid-19 pandemic is a unique and extraordinary situation for the globe, which has potentially disrupted almost all aspects of life. In this global crisis, the tourism and…
Abstract
Purpose
Covid-19 pandemic is a unique and extraordinary situation for the globe, which has potentially disrupted almost all aspects of life. In this global crisis, the tourism and hospitality sector has collapsed in almost all parts of the world, and the same is true for India. Therefore, this paper aims to investigate the impact of Covid-19 on the Indian tourism industry.
Design/methodology/approach
This study develops an appropriate model to forecast the expected loss of foreign tourist arrivals (FTAs) in India for 10 months. Since the FTAs follow a seasonal trend, seasonal autoregressive integrated moving average (SARIMA) method has been employed to forecast the expected FTAs in India from March 2020 to December 2020. The results of the proposed model are then compared with the ones obtained by Holt-Winter's (H-W) model to check the robustness of the proposed model.
Findings
The SARIMA model seeks to manifest the monthly arrival of foreign tourists and also elaborates on the progressing expected loss of foreign tourists arrive for the next three quarters is approximately 2 million, 2.3 million and 3.2 million, respectively. Thus, in the next three quarters, there will be an enormous downfall of FTAs, and there is a need to adopt appropriate measures. The comparison demonstrates that SARIMA is a better model than H-W model.
Originality/value
Several studies have been reported on pandemic-affected tourism sectors using different techniques. The earlier pandemic outbreak was controlled and region-specific, but the Covid-19 eruption is a global threat having potential ramifications and strong spreading power. This work is one of the first attempts to study and analyse the impact of Covid-19 on FTAs in India.
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Niklas Humble and Peter Mozelius
The conducted examination of programming affordances and constraints had the purpose of adding knowledge and value that facilitate the on-going national curricula revision;…
Abstract
Purpose
The conducted examination of programming affordances and constraints had the purpose of adding knowledge and value that facilitate the on-going national curricula revision; knowledge that also could be of general interest outside the Swedish K-12 context.
Design/methodology/approach
With a qualitative approach, the study was conducted as a document analysis where submitted lesson plans were the base for a directed content analysis.
Findings
This study presents findings on how the involvement of programming in mathematics and technology have potential to foster engagement and motivation among students. Findings also indicate that the implementation of programming can develop important general skills that go beyond the boundaries of mathematics and technology. Moreover, the identified constraints could be valuable to improve the on-going curriculum development for K-12 mathematics and technology.
Research limitations/implications
This qualitative study was conducted on a relatively small number of teachers where the majority has taken the courses on a voluntary basis. An important complement would be to conduct a larger quantitative study with data from a more general sample of K-12 teachers.
Practical implications
Results and discussions provide guidance for K-12 teachers and other stakeholders who want to introduce programming as a complementary tool in teaching and learning activities.
Social implications
The study has a contribution to the on-going implementation of the Swedish national curricula for K-12 mathematics and technology.
Originality/value
During the last years, many studies have been published on teacher training in programming, and how the training can be improved. This study goes beyond the actual teacher training and examine aspects teachers translate to theirs daily work after completing the training.
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