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1 – 10 of over 4000Weiqiang Xue, Jingfeng Shen and Yawen Fan
The transient loads on the spherical hybrid sliding bearings (SHSBs) rotor system during the process of accelerating to stable speed are related to time, which exhibits a complex…
Abstract
Purpose
The transient loads on the spherical hybrid sliding bearings (SHSBs) rotor system during the process of accelerating to stable speed are related to time, which exhibits a complex transient response of the rotor dynamics. The current study of the shaft center trajectory of the SHSBs rotor system is based on the assumption that the rotational speed is constant, which cannot truly reflect the trajectory of the rotor during operation. The purpose of this paper truly reflects the trajectory of the rotor and further investigates the stability of the rotor system during acceleration of SHSBs.
Design/methodology/approach
The model for accelerated rotor dynamics of SHSBs is established. The model is efficiently solved based on the fourth-order Runge–Kutta method and then to obtain the shaft center trajectory of the rotor during acceleration.
Findings
Results show that the bearing should choose larger angular acceleration in the acceleration process from startup to the working speed; rotor system is more stable. With the target rotational speed increasing, the changes in the shaft trajectory of the acceleration process are becoming more complex, resulting in more time required for the bearing stability. When considering the stability of the rotor system during acceleration, the rotor equations of motion provide a feasible solution for the simulation of bearing rotor system.
Originality/value
The study can simulate the running stability of the shaft system from startup to the working speed in this process, which provides theoretical guidance for the stability of the rotor system of the SHSBs in the acceleration process.
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Abstract
Purpose
The performance of oil-filled pressure cores is very much affected by the corrugated diaphragm and the oil filling volume. The purpose of this paper is to show the effects of different corrugated diaphragms, different oil filling volumes and different treatments of the corrugated diaphragms on the performance of pressure sensors.
Design/methodology/approach
Pressure-sensitive cores with different diaphragm diameters, different diaphragm ripple numbers and different oil filling volumes are produced, and thermal cycling is introduced to improve the diaphragm performance, and finally the performance of each pressure-sensitive core is tested and the test data are analyzed and compared.
Findings
The experimental results show that the larger the diameter of the corrugated diaphragm used for encapsulation, the better the performance. For pressure-sensitive cores using smaller diameter corrugated diaphragms, the performance of one corrugation is better than that of two corrugations. When the number of corrugations and the diameter are the same size, the performance of the outer ring of the diaphragm with concave corrugations is better than that with convex corrugations. At the same time, the diaphragm after thermal cycling treatment and appropriate reduction of encapsulated oil filling can improve the performance of the pressure-sensitive core.
Originality/value
By exploring the effects of corrugated diaphragm and oil filling volume on the performance of oil-filled pressure cores, the design of oil-filled pressure sensors can be guided to improve sensor performance.
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Douglas Ramalho Queiroz Pacheco
This study aims to propose and numerically assess different ways of discretising a very weak formulation of the Poisson problem.
Abstract
Purpose
This study aims to propose and numerically assess different ways of discretising a very weak formulation of the Poisson problem.
Design/methodology/approach
We use integration by parts twice to shift smoothness requirements to the test functions, thereby allowing low-regularity data and solutions.
Findings
Various conforming discretisations are presented and tested, with numerical results indicating good accuracy and stability in different types of problems.
Originality/value
This is one of the first articles to propose and test concrete discretisations for very weak variational formulations in primal form. The numerical results, which include a problem based on real MRI data, indicate the potential of very weak finite element methods for tackling problems with low regularity.
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Under pressure on cost-of-living issues, Canberra is reviewing competition laws to see what effect market dominance may be having in a handful of major sectors, including banking…
Details
DOI: 10.1108/OXAN-DB286078
ISSN: 2633-304X
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Geographic
Topical
Ceri Pimblett and Lisa Ogilvie
The purpose of this paper is to examine recovery through lived experience. It is part of a series that explores candid accounts of addiction and recovery to identify important…
Abstract
Purpose
The purpose of this paper is to examine recovery through lived experience. It is part of a series that explores candid accounts of addiction and recovery to identify important components in the recovery process.
Design/methodology/approach
The G-CHIME model comprises six elements important to addiction recovery (growth, connectedness, hope, identity, meaning in life and empowerment). It provides a standard against which to consider addiction recovery, having been used in this series, as well as in the design of interventions that improve well-being and strengthen recovery. In this paper, a first-hand account is presented, followed by a semi-structured e-interview with the author of the account. Narrative analysis is used to explore the account and interview through the G-CHIME model.
Findings
This paper shows that addiction recovery is a remarkable process that can be effectively explained using the G-CHIME model. The significance of each component in the model is apparent from the account and e-interview presented.
Originality/value
Each account of recovery in this series is unique and, as yet, untold.
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Carla Chalhoub and Ibrahim Farah
This paper aims to study the after-effects of the crises hit by the Lebanese population and the solutions implemented to alleviate the ensuing problems on resource sharing in…
Abstract
Purpose
This paper aims to study the after-effects of the crises hit by the Lebanese population and the solutions implemented to alleviate the ensuing problems on resource sharing in Lebanese libraries.
Design/methodology/approach
Questionnaire to academic libraries. Nine libraries in Lebanon offer resource sharing services; all nine are academic. A self-administered questionnaire was sent to these nine libraries; eight responded. A semi-quantitative approach was used to analyze the responses. The questionnaire was administered through Microsoft Forms. The form was designed to include dichotomous questions for the sake of quantitative analysis and a short answer format that allowed responders to provide additional details. American University of Beirut Data. The access services department at the American University of Beirut Jafet Library compiles on a daily basis interlibrary loan statistics. The compiled data were divided into two groups: duration of two fiscal years prior to June 2020; and from June 2020 to June 2022. June 2020 was used as a cutoff date after which the interlibrary loan initiatives in response to COVID-19 were implemented. The services that were analyzed were RSCVD, OCLC WorldShare ILL profiled groups, Emergency Temporary Access Service for HathiTrust members and Open Access Services from vendors.
Findings
Libraries in Lebanon were able to continue providing resource-sharing services with a minimal budget due to four major initiatives and through the help of the international resource-sharing community.
Originality/value
Limited publication about inter library loan in Lebanese Libraries. The pandemic hit economies worldwide; however, Lebanon got hit by three synergetic crises, and the initiatives were instrumental in drastically reducing resource sharing expenditure without affecting the interlibrary loan fill rate.
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Nafiya Guden and Farzad Safaeimanesh
This theme issue sought to find answers to the question: What should be the role of tourism education social structures to create and support collaborative learning environments…
Abstract
Purpose
This theme issue sought to find answers to the question: What should be the role of tourism education social structures to create and support collaborative learning environments and the tourism sector?
Design/methodology/approach
A thematic analysis of the articles in this collection draws together the key outcomes related to the strategic question, with particular reference to the contribution to knowledge, important to generate ideas and conceptual researches that will support institutions teaching tourism and hospitality. Archive research results and recommendations to encourage the collaboration of different stakeholders involved in sustainable tourism development. Most importantly to raise awareness of the question of what educators are doing in tourism education for social, organizational structures in learning environments and the actual tourism sector.
Findings
Two key players, the educator and sector has been challenged to consider their roles in education as well as depicting the role of social and organizational structures that support the students, institutions and the tourism sector. The main findings have proven the important role education plays for a truly sustainable tourism model, suggesting that it is not possible to create awareness of the sustainable development goals without incorporating them in the tourism education system with the support of information computer technology.
Originality/value
This paper reflects on the strategic question discussed in this theme issue, and it contains valid reviews, research studies by practitioners who are experienced in the field of tourism education with an opportunity to research, reflect and develop new possibilities in learning, mitigate negative points and increase positive tourism education roles for sustainable tourism development, in the destination and industry.
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Di Cheng, Yuqing Wen, Zhiqiang Guo, Xiaoyi Hu, Pengsong Wang and Zhikun Song
This paper aims to obtain the evolution law of dynamic performance of CR400BF electric multiple unit (EMU).
Abstract
Purpose
This paper aims to obtain the evolution law of dynamic performance of CR400BF electric multiple unit (EMU).
Design/methodology/approach
Using the dynamic simulation based on field test, stiffness of rotary arm nodes and damping coefficient of anti-hunting dampers were tested. Stiffness, damping coefficient, friction coefficient, track gauge were taken as random variables, the stochastic dynamics simulation method was constructed and applied to research the evolution law with running mileage of dynamic index of CR400BF EMU.
Findings
The results showed that stiffness and damping coefficient subjected to normal distribution, the mean and variance were computed and the evolution law of stiffness and damping coefficient with running mileage was obtained.
Originality/value
Firstly, based on the field test we found that stiffness of rotary arm nodes and damping coefficient of anti-hunting dampers subjected to normal distribution, and the evolution law of stiffness and damping coefficient with running mileage was proposed. Secondly stiffness, damping coefficient, friction coefficient, track gauge were taken as random variables, the stochastic dynamics simulation method was constructed and applied to the research to the evolution law with running mileage of dynamic index of CR400BF EMU.
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The intent of this Practice Briefing is to provide clarity on drivers of property pricing in a changing economic environment. The principal basis of this analysis is to…
Abstract
Purpose
The intent of this Practice Briefing is to provide clarity on drivers of property pricing in a changing economic environment. The principal basis of this analysis is to investigate how properties have been priced relative to interest rates over the long haul. Such an insight may help investors navigate the world of property investment in a post zero interest-rate policy (ZIRP) world.
Design/methodology/approach
This practice briefing is an overview of the role of economic drivers in pricing property in different economic eras pre- and post-ZIRP. It looks at returns over time relative to risk criteria and growth.
Findings
This briefing is a review of property pricing and its relationship to economic drivers and discusses the concept of return premiums as a market indicator to spot under/over-priced property assets in the market.
Practical implications
This briefing considers the implications of identifying salient and pertinent market indicators over time as bellweathers for property pricing. Good property investment is grounded in understanding when assets are under and overpriced relative to investors’ expectations of growth and returns going forward. An understanding of markets and the current indicators thereof can provide investors with insights into those criteria.
Originality/value
This provides guidance on how to interpret markets and get an understanding of property pricing over time.
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Bo You and Qi Si Wang
The purpose of this paper is to investigate the distribution characteristics of airflow in mine ventilation suits with different pipeline structures when the human body is bent at…
Abstract
Purpose
The purpose of this paper is to investigate the distribution characteristics of airflow in mine ventilation suits with different pipeline structures when the human body is bent at various angles. On this basis, the stress points are extracted to investigate the pressure variation of a ventilation suit under different ventilation rates and pipeline structures.
Design/methodology/approach
Based on the three-dimensional human body scanner, portable pressure test and other instruments, a human experiment was conducted in an artificial cabin. The study analyzed and compared the distribution characteristics of clearance under three different pipeline structures, as well as the pressure variation of the ventilation suit.
Findings
The study found that the clearance in front of two pipeline structures gradually increased in size as the degree of bending increased, and there was minimal clearance in the chest and back. The longitudinal structure exhibits a significant decrease in clearance compared to the spiral structure. The pressure value of the spiral pipeline structure with the same ventilation volume is low, followed by the transverse structure, while the longitudinal structure has the highest pressure value. The increase in clothing pressure value of a spiral pipeline structured ventilation suit with varying ventilation volumes is minimal.
Originality/value
The ventilation suit has a promising future as a type of personal protective equipment for mitigating heat damage in mines. It is of great value to study the pipeline structure of the ventilation suit for human comfort.
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