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This paper aims to carry out tribological experiments to explore the applications of femtosecond laser surface texturing technology on rock bit sliding bearing to enhance the lifetime and working performance of rock bit sliding bearing under high temperature and heavy load conditions.

Surface textures on beryllium bronze specimen were fabricated by femtosecond laser ablation (800 nm wavelength, 40 fs pulse duration, 1 kHz pulse repetition frequency), and then the tribological behaviors of pin-on-disc configuration of rock bit bearing were performed with 20CrNiMo/beryllium bronze tribo-pairs under non-Newtonian lubrication of rock bit grease.

The results showed that the surface texture on beryllium bronze specimens with specific geometrical features can be achieved by optimizing femtosecond laser processing via adjusting laser peak power and exposure time; more than 52 per cent of friction reduction was obtained from surface texture with a depth-to-diameter ratio of 0.165 and area ratio of 5 per cent at a shear rate of 1301 s−1 under the heavy load of 20 MPa and high temperature of 120°C, and the lubrication regime of rock bit bearing unit tribo-pairs was improved from boundary to mixed lubrication, which indicated that femtosecond laser ablation technique showed great potential in promoting service life and working performance of rock bit bearing.

Femtosecond laser-irradiated surface texture has the potential possibility for application in rock bit sliding bearing to improve the lubrication performance. Because proper micro dimples showed good lubrication and wear resistance performance for unit tribo-pairs of rock bit sliding bearing under high temperature, heavy load and non-Newtonian lubrication conditions, which is very important to improve the efficiency of breaking rock and accelerate the development of deep-water oil and gas resources.

The purpose of this paper is to examine the influence of several intrinsic motivations driving consumers' intention to buy using a mobile app, namely: shopping gamification, focussed attention, shopping enjoyment and socialness, through the mediating role of shopping engagement. The online shopping experience is investigated in its dual role as direct driver of the intention to buy using a mobile app and as moderator of the shopping engagement – intention to buy using a mobile app path.

The empirical analysis was performed in China due to the extensive usage of mobile shopping apps amongst the Chinese population. A structural equation model was estimated on 893 valid and complete structured questionnaires collected amongst a sample of Chinese consumers.

Findings confirm that intrinsic motivations (i.e. shopping gamification, focussed attention, shopping enjoyment and socialness) indirectly influence the intention to buy using a mobile app channelled by shopping engagement. Most remarkably, results show that the online shopping experience positively moderates the shopping engagement – intention to buy using a mobile app path.

The novelty of the paper lies in the conceptual and empirical evidence provided on shopping gamification, within the retailing marketing domain. The study investigates other related intrinsic motivations that jointly with shopping gamification directly influence shopping engagement and indirectly impact mobile shopping intention. The paper provides insights into the moderating role of online shopping experience, a key aspect when the challenge concerning gamification is considered.

The paper targets on providing new experimental data for validation of the well-established mathematical models within the framework of the lattice Boltzmann method (LBM), which are applied to problems of casting processes in complex mould cavities.

An experimental campaign aiming at the free-surface flow within a system of narrow channels is designed and executed under well-controlled laboratory conditions. An in-house lattice Boltzmann solver is implemented. Its algorithm is described in detail and its performance is tested thoroughly using both the newly recorded experimental data and well-known analytical benchmark tests.

The benchmark tests prove the ability of the implemented algorithm to provide a reliable solution when the surface tension effects become dominant. The convergence of the implemented method is assessed. The two new experimentally studied problems are resolved well by simulations using a coarse computational grid.

A detailed set of original experimental data for validation of computational schemes for simulations of free-surface gravity-driven flow within a system of narrow channels is presented.

The rostrum of a paddlefish provides hydrodynamic stability during feeding process in addition to detect the food using receptors that are randomly distributed in the rostrum. The exterior tissue of the rostrum covers the cartilage that surrounds the bones forming interlocking star shaped bones.

The aim of this work is to assess the mechanical behavior of four finite element models varying the type of formulation as follows: linear-reduced integration, linear-full integration, quadratic-reduced integration and quadratic-full integration. The paper also presents the load transfer mechanisms of the bone structure of the rostrum. The base material used in the study was steel with elastic–plastic behavior as a homogeneous material before applying materials properties that represents the behavior of bones, cartilages and tissues.

Conclusions are based on comparison among the four models. There is no significant difference between integration orders for similar type of elements. Quadratic-reduced integration formulation resulted in lower structural stiffness compared with linear formulation as seen by higher displacements and stresses than using linearly formulated elements. It is concluded that second-order elements with reduced integration are the alternative to analyze biological structures as they can better adapt to the complex natural contours and can model accurately stress concentrations and distributions without over stiffening their general response.

The use of advanced computational mechanics techniques to analyze the complex geometry and components of the paddlefish rostrum provides a viable avenue to gain fundamental understanding of the proper finite element formulation needed to successfully obtain the system behavior and hot spot locations.

This study aims to propose a semiempirical and semitheoretical cyclic compaction constitutive model of coarse-grained soil filler for the high-speed railway (HSR) subgrade under cyclic load.

According to the basic framework of critical state soil mechanics and in view of the characteristics of the coarse-grained soil filler for the HSR subgrade to bear the train vibration load repeatedly for a long time, the hyperbolic empirical relationship between particle breakage and plastic work was derived. Considering the influence of cyclic vibration time and stress ratio, the particle breakage correction function of coarse-grained soil filler for the HSR subgrade under cyclic load was proposed. According to the classical theory of plastic mechanics, the shearing dilatation equation of the coarse-grained soil filler for the HSR subgrade considering particle breakage was modified and obtained. A semiempirical and semitheoretical cyclic compaction constitutive model of coarse-grained soil filler for the HSR subgrade under cyclic load was further established. The backward Euler method was used to discretize the constitutive equation, build a numerical algorithm of “elastic prediction and plastic modification” and make a secondary development of the program to solve the cyclic compaction model.

Through the comparison with the result of laboratory triaxial test under the cyclic loading of coarse-grained soil filler for the HSR subgrade, the accuracy and applicability of the cyclic compaction model were verified. Results show that the model can accurately predict the cumulative deformation characteristics of coarse-grained soil filler for the HSR subgrade under the train vibration loading repeatedly for a long time. It considers the effects of particle breakage and stress ratio, which can be used to calculate and analyze the stress and deformation evolution law of the subgrade structure for HSR.

The research can provide a simple and practical method for calculating deformation of railway under cyclic loading.

The subject of this paper is the idea of Brain–Computer Interface (BCI). The main goal is to assess the potential impact of BCI on the design, use and evaluation of information retrieval systems operating in libraries.

The method of literature review was used to establish the state of research. The search according to accepted queries was carried out in the Scopus database and complementary in Google Scholar. To determine the state of research on BCI on the basis of library and information science, a specialist LISTA abstract database was also searched. The most current papers published in the years 2015–2019 in the English language or having at least an abstract in this language were taken into account.

The analysis showed that BCI issues are extremely popular in subject literature from various fields, mainly computer science, but practically does not occur in the context of using this technology in information retrieval systems.

Due to the fact that BCI solutions are not yet implemented in libraries and are rarely the subject of scientific considerations in the field of library and information science, this article is mainly based on literature from other disciplines. The goal was to consider how much BCI solutions can affect library information retrieval systems. The considerations presented in this article are theoretical in nature due to the lack of empirical materials on which to base. The author's assumption was to initiate a discussion about BCI on the basis of library and information science, not to propose final solutions.

The results can be widely used in practice as a framework for the implementation of BCI in libraries.

The article can help to facilitate the debate on the role of implementing new technologies in libraries.

The problem of BCI is very rarely addressed in the subject literature in the field of library and information science.

The combined effects of several complex phenomena cause the deterioration of elements in steel hydraulic structures (SHSs) within the US lock system: corrosion, cracking and fatigue, impact and overloads. Predicting the future condition state of these structures by the use of current condition state inspection data can be achieved through the probabilistic chain deterioration model. The purpose of this study is to derive the transition probability matrix using final elements modeling of a miter gate.

If predicted accurately, this information would yield benefits in determining the need for rehabilitation or replacement of SHS. However, because of the complexity and difficulties on obtaining sufficient inspection data, there is a lack of available condition states needed to formulate proper transition probability matrices for each deterioration case.

This study focuses on using a three-dimensional explicit finite element analysis (FEM) of a miter gate that has been fully validated with experimental data to derive the transition probability matrix when the loss of flexural capacity in a corroded member is simulated.

New methodology using computational mechanics to derive the transition probability matrices of navigation steel structures has been presented.

The difficulty of deriving the transition probability matrix to perform a Markovian analysis increases when limited amount of inspection data is available. The used state of practice FEM to derive the transition probability matrix is not just necessary but also essential when the need for proper maintenance is required but limited amount of the condition of the structural system is unknown.

Gamification is the use of game elements in different contexts. It is also a tool with potential application in several areas, including training and development. From this reference, this study has a main objective to identify a perception of efficiency and the measurable results in the process of gamification in training and development actions.

The quantitative stage of the research sought to investigate the perception of efficiency of professionals who have already undergone gamified training, collected through an online form with responses on a Likert scale and treated with the Minitab Statistical Software. The qualitative stage, on the other hand, identifies the perception of results through classification with professionals who develop gamified training, with the results found in the content analysis techniques.

The compiled results confirmed the presence of engagement and its influence on motivation as one of the advantage points for the application of gamification. It was also possible to find in these results the relevance of design care for the game/training interaction to work effectively.

Among the trends of greatest incidence found in the research, are the possibility of associating gamification with virtual reality and augmented reality, as well as with simulators to enhance the experience lived by the player during training.

The present study aims to synthesize and conceptualize, through a systematic literature review (SLR), the current state of gamification knowledge in the tourism and hospitality (T&H) sector, providing a roadmap for future research recommendations for service research and practice.

The research is based on a systematic literature review and adopts a systematic quantitative approach to summarize existing evidence on gamification usage in the T&H sector, focusing on relevant service literature on gamification. The authors analyze 36 papers published between 2011 and 2019.

The authors synthesize existing knowledge into five themes describing gamification's role in T&H (Edutainment, Sustainable behavior, Engagement factors, Service provider-generated content and User-generated reviews). Then, a cross-analysis of the five themes reveals the pivotal elements (affordances, behavioral and psychological outcomes, and benefits) generated by gamification mechanics in T&H, simultaneously highlighting potential implications and relevant insights for service literature. The review identifies critical issues affecting gamification research and provides a future research agenda, considering opportunities for T&H and service research.

The study provides the first SLR investigating gamification in T&H. The findings present potential implications and relevant insights for T&H contributing to the construction of a more holistic understanding of gamification adoption in service research.

This paper provides an analytical account detailing the historical linkages between Chinese on both sides of the Sino-Hong Kong border from 1841 onwards and examining important incidents of collective actions in the colony and Canton.

Using annual reports published by the colonial administration in Hong Kong, especially those focusing on years that witnessed major incidents of anti-colonial agitations, this paper analyzes how British policymakers were confronted by collective actions mounted by Chinese in Canton and Hong Kong. Building on the works of prominent historians and utilizing the theoretical frameworks of analysts such as Charles Tilly (1978), the author examines if a Cantonese regional solidarity served as the foundation for popular movements, which in turn consolidated a rising Chinese nationalism when Canton and Hong Kong were the focal points of mass actions against imperialism.

Hong Kong Chinese workers were vanguards of the modern Chinese revolutions that transformed not just their homeland, but their lives, allegiances, and aspirations as Chinese in a domain under foreign jurisdiction on Chinese soil, as their actions were emulated by their compatriots outside of South China, thus starting a chain reaction that culminated in the establishment of the Nanjing regime.

This paper reveals that popular movements of Hong Kong Chinese possessed national and international importance, especially when they were supported by their Cantonese compatriots and the two leading Chinese political parties, the Kuomintang (KMT) and the Chinese Communist Party (CCP).