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This study aims to investigate the surface modification on 20CrMnTi gear steel individually treated by diamond-like carbon films and nitride coatings.

For this purpose, the mechanical properties of a-C:H, ta-C and AlCrSiN coatings are characterized by nano-indentation and scratch tests. The friction and wear behaviors of these three coatings are evaluated by ball-on-disc tribological experiments under dry contact conditions.

The results show that the a-C:H coating has the highest coating-substrate adhesion strength (495 mN) and the smoothest surface (Ra is about 0.045 µm) compared with the other two coatings. The AlCrSiN coating shows the highest mean coefficient of friction (COF), whereas the ta-C coating exhibits the lowest one (steady at about 0.16). The carbon-based coatings possess excellent self-lubricating properties compared with nitride ceramic ones, which effectively reduce the COF by about 64%. The major failure mode of carbon-based coatings in dry contact is slight abrasive wear. The damage of AlCrSiN coating is mainly adhesive wear and abrasive wear.

It is suggested that the carbon-based film can effectively improve the friction-reducing and wear resistance performance of the gear steel surface, which has a promising application prospect in the mechanical transmission field.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-05-2023-0129/

This paper aims to examine the effect of sesame oil (SO) on fatigue and mental health status in women with nonalcoholic fatty liver disease (NAFLD) undergoing a weight-loss diet.

In total, 60 women with NAFLD were randomly assigned to receive 30 g/day of either SO (n = 30) or sunflower oil (n = 30). All the patients received a hypocaloric diet (−500 kcal/day) for 12 weeks in a double-blinded controlled trial. Anthropometric indices, dietary intake, physical activity, fatigue and mental health status were measured at the baseline and the trial cessation.

In total, 53 participants completed the intervention. Significant reductions in anthropometric indices were observed in both groups (p-value = 0.001). Following SO, fatigue (p-value = 0.002), anxiety (p-value = 0.011) and depression (p-value = 0.013) scores were significantly reduced, while no significant changes were observed in stress scores.

In summary, the present study was conducted to assess the efficacy of SO consumption on fatigue and mental health status among patients with NAFLD. The results revealed SO consumption significantly reduced fatigue, anxiety and depression scores in comparison with the control group, but not for stress scores. Further clinical trials, different doses, with a longer duration of intervention, in different groups, are necessary to confirm the veracity of the results.

Coopetition (simultaneous cooperation and competition of actors) is still a relatively new concept in business, management, and tourism. However, several coopetition studies have focused on tourism and tourism destinations. Also, compilation literature reviews of tourism and tourism destinations have been published (Rusko, 2018). This chapter focuses on underlying coopetition networks of tourism and specifically of tourism destinations. Because of the typical features of tourism destinations, multifaceted connections in competition and cooperation – and coopetition – are present in everyday business and activities among actors of the destination. These coopetitive relationships cover several levels, they are present in micro, meso, macro, and meta level interplay of tourism destination. Furthermore, the analysis shows that several studies about coopetitive networks in tourism destinations do not use terms “macro” or “meta” though these seem to be the main levels of the studies. This only reveals the fertile dimensions of coopetitive networks in tourism. These various relationships form coopetitive networks that represent several dimensions and levels of actors, competition, cooperation, and coopetition. This chapter introduces these multifaceted perspectives of coopetition networks, which have been described in the contemporary literature about tourism and tourism destination.

Coopetition is a well-studied phenomenon in traditional enterprises. However, it lacks deepening in the social sphere, specifically on hybrid organizations (social and commercial goals). This paper analyzes the configuration of coopetition strategies in social enterprises and how these strategies can improve social value devolution.

The authors conducted a multicase study with Brazilian social enterprises and a social incubator. Semistructured interviews with founders of the social enterprises and the president of the incubator were the primary sources of evidence, supported by observations and secondary data.

The authors identified four main findings: (1) the social incubator induces coopetition among social enterprises; (2) coopetition is necessary to improve market performance; (3) coopetition is a natural strategy resulting from the activity of the social enterprise; (4) the behavior and context of social enterprises generate a new framework for coopetition formation. This framework comprises three stages of value: a social cooperation level to co-creation of value; second, a social competition level to the appropriation of value; and the third coopetition-balanced level to social value devolution.

The authors advance knowledge on coopetition in an exciting, underexplored context, social entrepreneurship. The authors highlight that the coopetition nature and outcome in social enterprises have specificities compared to traditional businesses. The authors also improve the understanding of social value devolution based on simultaneous cooperation and competition among small social enterprises, allowing theoretical and practical implications. Thus, they advance the recurring discussion in coopetition literature beyond the generation and appropriation of value.

The purpose of this study is to investigate the errors arising from the numerical treatment of model processes, paying particular attention to the impact of key system features including widely variable dispersion coefficients, spatiotemporal velocities of algal cells, and the aggregation of algae from single cells to large colonies. An advection–dispersion model has been presented to describe the vertical transport of colonial and motile harmful algae in a lake environment.

Model performance is examined for two different numerical treatments of the advective term: first-order upwind and quadratic upwind with a stability-preserving flux limiter (SMART). To determine how these schemes impact predictions, comparisons are made across a sequence of models with increasing complexity.

Using first-order upwinding for advection–dispersion calculations with a time oscillating velocity field leads to oscillatory numerical dispersion. Subjecting an initially uniform distribution of large-sized algal colonies to a spatiotemporal velocity creates a concentration pulse, which reaches a steady-state width at high-grid Peclet numbers when using the SMART scheme; the pulse exhibits contraction–expansion behavior throughout a velocity cycle at all Peclet numbers when using first-order upwinding. When aggregation dynamics are included with advection-dominated spatiotemporal transport, results indicate the SMART scheme predicts larger peak concentration values than those predicted by first-order upwind, but peak location and the time to large colony appearance remain largely unchanged between the two advective schemes.

To the best of the authors’ knowledge, this study is the first numerical investigation of a novel advection–dispersion model of vertical algal transport. In addition, a generalized expression for the effective dispersion coefficient of temporally variable flow fields is presented.

This paper aims to analyse the effects of events image from host communities’ perspective on the city’s overall image and the intention to recommend the events and the city as a tourism destination.

The research used a bivariate data analysis based on Spearman’s correlation and regression analysis to determine useful variables to predict the intention to recommend the city as a tourism destination. Data collection was face-to-face and online with a non-probabilistic sample of Viseu city residents, the second largest city in the central region of Portugal.

The findings had implications for researchers, governments and stakeholders. From the resident’s point of view, there is a high correlation between the overall city image and the intention to recommend it as a tourism destination. Event image and the intention to recommend the event participation affect the overall city image. Results point out the resident as natural promoters of events and their city if the local events have an appeal that generates their participation. Conclusions indicated that cities need to re-thinking tourism from the citizen’s perspective as staycation is a grown option.

Event image by host-city residents’ perceptions is an underdevelopment theme in the literature, although residents’ participation is essential to the success of most events. Local events can promote tourist citizenship and reinforce the positioning of tourism destinations, associating them with an image of desirable places to visit and live.

Limited by the types of sensors, the state information available for musculoskeletal robots with highly redundant, nonlinear muscles is often incomplete, which makes the control face a bottleneck problem. The aim of this paper is to design a method to improve the motion performance of musculoskeletal robots in partially observable scenarios, and to leverage the ontology knowledge to enhance the algorithm’s adaptability to musculoskeletal robots that have undergone changes.

A memory and attention-based reinforcement learning method is proposed for musculoskeletal robots with prior knowledge of muscle synergies. First, to deal with partially observed states available to musculoskeletal robots, a memory and attention-based network architecture is proposed for inferring more sufficient and intrinsic states. Second, inspired by muscle synergy hypothesis in neuroscience, prior knowledge of a musculoskeletal robot’s muscle synergies is embedded in network structure and reward shaping.

Based on systematic validation, it is found that the proposed method demonstrates superiority over the traditional twin delayed deep deterministic policy gradients (TD3) algorithm. A musculoskeletal robot with highly redundant, nonlinear muscles is adopted to implement goal-directed tasks. In the case of 21-dimensional states, the learning efficiency and accuracy are significantly improved compared with the traditional TD3 algorithm; in the case of 13-dimensional states without velocities and information from the end effector, the traditional TD3 is unable to complete the reaching tasks, while the proposed method breaks through this bottleneck problem.

In this paper, a novel memory and attention-based reinforcement learning method with prior knowledge of muscle synergies is proposed for musculoskeletal robots to deal with partially observable scenarios. Compared with the existing methods, the proposed method effectively improves the performance. Furthermore, this paper promotes the fusion of neuroscience and robotics.

This paper discusses the effectiveness of a consortium-based student mobility programme by investigating the impact of the Asian International Mobility for Students (AIMS) Programme. AIMS is a regional multilateral large-scale student mobility programme based on a consortium of 10 member countries and 87 member universities with the Southeast Asian Ministers of Education Organization Regional Centre for Higher Education and Development (SEAMEO RIHED) as a facilitator. Over 6,000 students have participated in a semester-long intra-regional student exchange under AIMS since 2010.

The study employed questionnaire surveys and semi-structured interviews to investigate the impact of AIMS and its advantages as a consortium-based student mobility programme.

It was found that AIMS significantly impacted member universities by accelerating their internationalisation processes through increasing the number of inbound and outbound students and courses offered in English and so on. AIMS has promoted harmonisation among the members by developing common procedures and guidelines, providing platforms for mutual sharing of experiences and good practices and capacity building of international relations offices. AIMS has also had a significant impact on students by enhancing their regional identity and knowledge about the region of Asia, contributing to their development as future regional and global citizens. As advantages of AIMS, member universities efficiently built a foundation for international collaboration with common procedures and guidelines and shared their experiences through such venues as Annual Review Meetings. Students also feel supported by having clear guidance and find programmes prepared by host universities and SEAMEO RIHED useful.

This study is unique in that it empirically studies the impact of one of Asia’s largest student mobility programmes for the first time by analysing large-scale qualitative and quantitative data.

As the consumer-centric approach is evolving in the 21st century, especially in the post-COVID-19 era, people seek unique experiences. Adopting co-creation in promoting a destination implies involving tourists, stakeholders and organisers in creating value for a product or service. The innovative strategy of co-creating experiences encourages tourists' engagement, leading to destination promotion. Some notable examples of co-creation in tourism are gastronomic tours, virtual tours and travel guides. This chapter aims at the significance of co-creating experiences at events that lead to destination promotion. Co-creation of experiences at events brings the spotlight from the stage to the audience and is considered the future of the experience economy. The study presents a case study of Jal Mahotsav in Madhya Pradesh, India. The study highlights the multi-stakeholder approach adopted by the authorities to co-create the event experience.

This chapter studies the tourism cluster of Majorca and its connection with collective entrepreneurship. To this end, the authors review the history of four world leading Spanish hotel companies, from their beginnings, in Majorca, in the 1950s, to their internationalization, in the 1980s and 1990s: Barceló, Meliá, Riu, and Iberostar. This allows us to identify common patterns of behaviour among them over time, which in turn illustrate the dynamics of the tourism cluster and the role played by its context. This qualitative and historical research allows us to make the following contributions: first, in line with other studies in the economic history of Spanish tourism, the four cases support the identification of Majorca as a tourism cluster. Second, the authors highlight several important characteristics of the island which reinforced and strengthened the cluster and boosted collective entrepreneurship, through an intense flow of information between the companies. Third, the authors illustrate coopetition as the key nature of the relationship between the clustered companies in a simultaneous process of competition and cooperation. Finally, the authors show how the strength of the tourism cluster, in Majorca, drove the companies to replicate the same dynamics and structures abroad.