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The purpose of this paper is to investigate the effect of round pits arrangement patterns on tribological properties of journal bearing. In this paper, the tribological behaviors of journal bearing with different arrangement patterns under lubrication condition were studied based on M-2000 friction and wear tester.

The friction and wear of journal bearing contact surface were simulated by ANSYS. The wear mechanism of bearing contact surfaces was investigated by the means of energy dispersive spectrum analysis on the surface morphology and friction and wear status of the journal bearing specimens by Scanning Electron Microscopy (SEM) and Energy Dispersive Spectrometer (EDS). Besides, the wearing capacity of the textured bearing was predicted by using the GM (1,1) and Grey–Markov model.

As the loads increase, the friction coefficient of journal bearing specimens decrease first and then increase slowly. The higher rotation speed, the lower friction coefficient and the faster temperature build-up. The main friction method of the bearing sample is three-body friction. The existence of texture can effectively reduce friction and wear. In many arrangement patterns, the best is 4# bearing with round pits cross-arrangement pattern. Its texturing diameters are 60 µm and 125 µm, and the spacing and depth are 200 µm and 25 µm, respectively. In addition, the Grey–Markov model prediction result is more accurate and fit the experimental value better.

The friction and wear mechanism is helpful for scientific research and engineers to understand the tribological behaviors and engineering applications of textured bearing. The wear capacity of textured bearing is predicted by using the Grey–Markov model, which provides technical help and theoretical guidance for the service life and reliability of textured bearing.

This paper aims to analyze the application of remotely piloted aircraft (RPA) for remote oil spill sensing.

This paper is an analysis of RPA strong points.

To increase the accuracy and eliminate potentially false contamination detection, which can be caused by external factors, an oil thickness measurement algorithm is used with the help of the multispectral imaging that provides high accuracy and is versatile for any areas of water and various meteorological and atmospheric conditions.

SWOT analysis of implementation of RPA for remote sensing of oil spills.

The use of RPA will improve the remote sensing of oil spills.

The concept of oil spills monitoring needs to be developed for quality data collection, oil pollution control and emergency response.

The research covers the development of a method and design of a device intended for taking samples and determining the presence of oil contamination in an aquatorium area; the procedure includes taking a sample from the water surface, preparing it for transportation and delivering the sample to a designated location by using the RPA. The objective is to carry out the analysis of remote oil spill sensing using RPA. The RPA provides a reliable sensing of oil pollution with significant advantages over other existing methods. The objective is to analyze the use of RPA employing all of their strong points. In this paper, technical aspects of sensors are analyzed, as well as their advantages and limitations.

To decrease wear and friction, zinc dialkyldithiophosphate (ZDDP) has been used in engine oil for several decades, but the mechanism of the tribofilm formation is still unclear. The purpose of this study is to characterize the chemical details of the tribofilm by using high-resolution approaching.

An ISO VG 100 mineral oil mixed with ZDDP was used in sliding tests on cylindrical roller bearings. Tribofilm formation was observed after 2 h of the sliding test. X-ray photoelectron spectroscopy (XPS) and atom probe tomography (APT) were used for chemical analysis of the tribofilm.

The results show that the ZDDP tribofilm consists of the common ZDDP elements along with iron oxides. A considerable amount of zinc and a small amount of sulfur were observed. In particular, an oxide interlayer with sulfur enrichment was revealed by APT between the tribofilm and the steel substrate. The depth profile of the chemical composition was obtained, and a tribofilm of approximately 40 nm thickness was identified by XPS.

A sulfur enrichment at the interface is observed by APT, which is beneath an oxygen enrichment. The clear evidence of the S interlayer confirms the hard and soft acids and bases principle.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-01-2020-0035/

This paper is supposed to provide a critical review of current research progress on thermal management in grinding of superalloys, and future directions and challenges. By understanding the current progress and identifying the developing directions, thermal management can be achieved in the grinding of superalloys to significantly improve the grinding quality and efficiency.

The relevant literature is collected from Web of Science, Scopus, CNKI, Google scholar, etc. A total of 185 literature is analyzed, and the findings in the literature are systematically summarized. In this case, the current development and future trends of thermal management in grinding of superalloys can be concluded.

The recent developments in grinding superalloys, demands, challenges and solutions are analyzed. The theoretical basis of thermal management in grinding, the grinding heat partition analysis, is also summarized. The novel methods and technologies for thermal management are developed and reviewed, i.e. new grinding technologies and parameter optimization, super abrasive grinding wheel technologies, improved lubrication, highly efficient coolant delivery and enhanced heat transfer by passive thermal devices. Finally, the future trends and challenges are identified.

Superalloys have excellent physical and mechanical properties, e.g. high thermal stability, and good high-temperature strength. The superalloys have been broadly applied in the aerospace, energy and automobile industries. Grinding is one of the most important precision machining technologies for superalloy parts. Owing to the mechanical and physical properties of superalloys, during grinding processes, forces are large and a massive heat is generated. Consequently, the improvement of grinding quality and efficiency is limited. It is important to conduct thermal management in the grinding of superalloys to decrease grinding forces and heat generation. The grinding heat is also dissipated in time by enhanced heat transfer methods. Therefore, it is necessary and valuable to holistically review the current situation of thermal management in grinding of superalloys and also provide the development trends and challenges.

The purpose of this paper is to analyze the micro-motion of the cylinder block.

Based on the elasto-hydrodynamic lubrication, a numerical model for the cylinder block/valve plate interface is proposed, with consideration of the elastic deformations, the pressure-viscosity effect and asperity contacts. The influence-function method is applied to calculating the actual deformations of the cylinder block and the valve plate. The asperity contact model simplified from Greenwood assumption is introduced into the numerical model. Furthermore, the relationship between the micro-motion and the operating condition, the sealing belt width is discussed, respectively.

The results show an increase in the discharge pressure causes the tilt state and the vibrating motion getting worse, which can be eased by improving the rotational speed, the sealing belt width and the ratio of external and internal sealing belt width.

The proposed research can provide a theoretical reference for the optimizing design of cylinder block/valve plate pair.

Sex tourism is well documented in the literature, but what about porn tourism? Whether it is a Ping Pong show in Phuket or the Banana show in Amsterdam, porn and tourism have an encounter and gaze no different from the Mona Lisa in the Louvre or magnificent views of New Zealand’s Southern Alps. The paper aims to discuss these issues.

This paper explores the intersections of tourism, porn and the future as a conceptual framework.

Four intersections are derived from the conceptual framework. Intersection 1, the Future of Tourism, portrays the evolution of tourism and explores its technological future. Interaction 2, Porn in Tourism, distinguishes between soft- and hard-core porn tourism. Intersection 3, Portraying Porn as a Future Dimension, delves into futurism, science fiction and fantasy. The fourth intersection, the Future Gaze, conveys the thrust of the paper by exploring how technological advancement blends with authenticity and reality. Thus the porn tourist seeks both the visual and the visceral pleasures of desire. The paper concludes with four future gazes of porn tourism, The Allure of Porn, The Porn Bubble, Porn as Liminal Experience and Hardcore.

The originality of this paper is that this is the first paper to systematically examine porn tourism beyond sex tourism overlaying with a futures dimension. Porn tourists actively seek to experience both visual and visceral pleasures. Tourism and pornography both begin with the gaze. The gaze is an integral component of futures thinking. Technology is changing us, making us smarter, driving our thirst for liminal experiences. Like the transition from silent movies to talking pictures the porn tourism experience of the future is likely to involve more of the bodily senses.

This article introduces the Special Issue on Sustainable Management of Heritage Buildings in long-term perspective.

It starts by reviewing the gaps in knowledge and practice which led to the creation and implementation of the research project SyMBoL—Sustainable Management of Heritage Buildings in long-term perspective funded by the Norwegian Research Council over the 2018–2022 period. The SyMBoL project is the motivation at the base of this special issue.

The editorial paper briefly presents the main outcomes of SyMBoL. It then reviews the contributions to the Special Issue, focussing on the connection or differentiation with SyMBoL and on multidisciplinary findings that address some of the initial referred gaps.

The article shortly summarizes topics related to sustainable preservation of heritage buildings in time of reduced resources, energy crisis and impacts of natural hazards and global warming. Finally, it highlights future research directions targeted to overcome, or partially mitigate, the above-mentioned challenges, for example, taking advantage of no sestructive techniques interoperability, heritage building information modelling and digital twin models, and machine learning and risk assessment algorithms.

There is growing scholarly discourse towards COVID-19 pandemic and creative entrepreneurship in the perspectives of Global South. Extant literature lacks sufficient empirical evidence on the subject matter. This paper therefore provides insights into business models and business model shifts in response to the COVID-19 pandemic among creative entrepreneurs in Ghana.

In working towards achieving the purpose of the study, a qualitative design was deployed. Four artistic communities in three regions were understudied. The study conducted working interviews, Focus Group Discussions and field observations on the creative entrepreneurs.

The results showed a unique business model that captured ministries, agencies and departments; traditional authorities, foreigners and the diaspora community as key creative partners. The creative entrepreneurs equally proposed value via quality deliveries, attractive pattern mix, pure handy crafts, mart finishing, imbibing culture into productions and symbolic meanings. Their key activities include cutting and gluing, sewing and coloring, sketching and prototyping, annual Kente festivals, film shooting and editing. The creatives stream revenue through sales, advances, profit margins, contracts, gate proceeds, loans, friends and family support. The results also point at a regime of business model shifts among the creatives, deploying digitalization and diversification in response to the COVID-19 pandemic.

The research by design is limited to the qualitative tradition; despite knowing well about the quantitative approach that could have provided a wider scope and coverage for effective generalizability. Certainly, it would be of future research interest to design a comparative mix-method study to achieve a wider coverage feat. Indeed, the paper does achieve the goal of providing an original empirical account, hence making a valid contribution to knowledge in the area of study.

The knowledge on demystified business models relative to the Ghanaian creative entrepreneurs has practical implications for practice: first, it generates a ground-up knowledge as to what creative entrepreneurial business models are, why they exist and exactly how to create one in a Global South perspective.

These creative business models and the COVID-19 induced model shifts among the Ghanaian creative entrepreneurs imply continuous creative livelihoods, sustainable business models and assurance for innovation in creative entrepreneurship space.

The study is of high scientific value, creative entrepreneurial essence and public interest to better demystify creative entrepreneurial business models and theoretically framed them. It offers strong empirical evidence on COVID-19 induced business model shifts. These creative business models and the COVID-19 induced model shifts among the Ghanaian creative entrepreneurs imply continuous creative livelihoods, sustainable business models and assurance for innovation in creative entrepreneurship space.

Recent research has demonstrated that people are more likely to engage with fatty food content online. One way health advocates might facilitate engagement with healthier, calorie-light foods is to alter how people process food media. This research paper aims to investigate the moderating role of viewer mindset on consumer responses to digital food media.

Two experiments were conducted by manipulating the caloric density of food media content and/or one’s mindset before viewing.

Results show that the relationship between nutrition and engagement is moderated by consumer mindset, where activating a more calculative mindset before exposure can elevate social media engagement for calorie-light food media content.

These findings contribute to the domain of obesogenic digital environments and the role of nutrition in consuming food media. By examining how mindsets interact with affective evaluations, this work demonstrates that a default mindset based on instinct can be shifted and thus alter subsequent behavioral intentions.

This work provides insight into what can boost the visibility and engagement of healthy food content on social media. Marketers can help promote healthier food media by cueing consumers to think more deliberately before exposure.

This research builds on recent work by demonstrating how to boost engagement with healthy foods on social media by cueing a more thoughtful mindset.