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Tantalum is a kind of metal material with moderate hardness, high ductility, small thermal expansion coefficient, excellent corrosion resistance and outstanding biocompatibility. The purpose of this study is that its tribological performance could be tested and analyzed so as to use it in different fields.

The friction resistance of a-Ta under dry friction conditions was tested at different roads. The relationships between load and friction coefficient, wear rate and two-dimensional shape of wear scars were studied.

The stable Ta₂O₅ film with lubrication effect was generated in the process of friction. And, the larger the test load, the more Ta₂O₅ would be generated.

This work lays a theoretical foundation for tantalum as an excellent wear-resistant material.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-02-2023-0047/

This paper aims to develop an optimal buyback promotion strategy for enterprises, including multibuyback strategy and self-buyback strategy, taking both the consumer's multichannel psychological acquisition attributes and remaining market into account.

Based on the game theory and Hotelling model, the authors formulate a new model to study the equilibrium of different buyback models, given the utility maximization of the consumers, the profit maximization and the constraint on nondecreasing market share of the enterprises, and the authors conduct comparative analysis.

Intuitively, enterprises buying back products of other brands would appeal to some consumers. However, the authors find that after implementing the multibuyback scheme, enterprises may not be able to seize competitors' markets or even lose their original customer base in the context considered in this article counterintuitive. In addition, the size of remaining market share and the consumer's multichannel psychological acquisition affect the choice of buyback promotion strategies. Moreover, after implementing multibuyback scheme, customers with old products subsidize those who receive additional discounts. Finally, the authors point out that the buyback strategy choices of companies with different goal-oriented are diverse.

This study has a very solid realistic background and provides guidance for enterprises to implement buyback promotion strategies. In addition, the authors unearth new influencing factors to provide a reasonable explanation for different buyback strategies in reality.

To the best of the authors’ knowledge, this study is one of the first to explore the multibuyback promotion strategy as a new buyback method, where the two influencing factors the authors have not been proposed so far.

Enterprises in the digital context attach importance to the participation of heterogeneous subjects in co-creation activities. As the core source of organizational innovation, employees are bound to assume responsibilities or provide role value in the process of digital innovation. While employee-driven digital innovation frameworks are being explored, together with research on employee innovation behavior mostly focusing on the “net effect” of single-level variables on outcomes.

Following the interaction logic of employee level and organizational level, this study applies ability, motivation and opportunity (AMO) theory and fuzzy set qualitative comparative analysis to explore the influence of various digitization related factors' conditional configuration on employees' digital innovation behavior.

The results indicate that type of “self-motivation with multiple supports”, “organization-driven with digital oriented” and “digital-driven with ambidextrous complementary” constitute the configuration that drives high digital innovation behavior, while type of “cognitive deficit with environmental slack” and “fuzzy motivation with opportunity misapplication” constitute the configuration that drives nonhigh digital innovation behavior.

This conclusion enriches the theoretical research on digital innovation that regards individuals as action potentials and provides important guidance for how to cultivate and activate employees' digital innovation behaviors in management practice.

The purpose of this paper is to introduce the modeling and implementation of a novel multimode amphibious robot, which is used for patrol and beach garbage cleaning in the land–water transition zone.

Starting from the design idea of multimode motion, the robot innovatively integrates the guiding fin and wheel together, is driven by the same motor and can achieve multimodal motion such as land, water surface and underwater with only six actuated degrees of freedom. The robot dispenses with the transmission mechanism by directly connecting the servo motor with a reducer to the actuator, so it has the characteristics of simplifying the structure and reducing the quality. And to the best of the authors' knowledge, the design of the robot can be considered the minimal configuration of amphibious robots with the same locomotion capabilities.

Based on the classical assumptions of underwater dynamics analysis, this paper uses basic airfoil theory to analyze the dynamics of the robot’s horizontal and vertical motions and establishes its simplified dynamics model. Also, the underwater motion of the robot is simulated, and the results are in good agreement with the existing research results. Finally, to verify the feasibility of the robot, a prototype is implemented and fully evaluated by experiments. Experimental results show that the robot can reach the maximum speed of 2.5 m/s and 0.3 m/s on land and underwater, respectively, proving the effectiveness of the robot.

The robot has higher work efficiency with the powerful multimode motion, and its simplified structure makes it more stable while costing less.

Post-merger integration (PMI) is driven by coevolving processes. This paper examines the coevolution of dynamic integration strategy and network reconstruction and explores how these processes systematically enable emerging market acquirers to upgrade innovation capabilities.

This paper conducts a multi-case study based on four Chinese overseas acquisitions of manufacturing firms. The data were collected from interviews and archival documentation.

This study develops a coevolutionary framework of dynamic integration strategy and network reconstruction to explain processes and mechanisms of an acquirer’s innovation capability upgrading. This framework identifies three network motivations, namely, network access, network connection and network synergy. Under different network motivations, dynamic transitions of the acquirer’s integration strategy coevolve with multi-level reconstruction of its networks. Collectively, they are important mechanisms driving innovation capability moves from imitation innovation to asportation and reimitation innovation and then to independent innovation.

This paper responds to a recent call for more insights into the dynamics of PMI and contributes to the research on emerging market multinational corporations’ post-acquisition integration. By integrating the M&A and networks literature, the paper provides evidence of unexplored mechanism of network changes during PMI. It reveals that how acquirers manage the dynamics of PMI to gradually achieve multi-level reconstruction of their networks. Based on a coevolutionary framework, the paper provides a process perspective on how the coevolution of PMI and network reconstruction promotes the upgrading of innovation capabilities.

The purpose of this paper is to introduce an improved system identification method for small unmanned helicopters combining adaptive ant colony optimization algorithm and Levy’s method and to solve the problem of low model prediction accuracy caused by low-frequency domain curve fitting in the small unmanned helicopter frequency domain parameter identification method.

This method uses the Levy method to obtain the initial parameters of the fitting model, uses the global optimization characteristics of the adaptive ant colony algorithm and the advantages of avoiding the “premature” phenomenon to optimize the initial parameters and finally obtains a small unmanned helicopter through computational optimization Kinetic models under lateral channel and longitudinal channel.

The algorithm is verified by flight test data. The verification results show that the established dynamic model has high identification accuracy and can accurately reflect the dynamic characteristics of small unmanned helicopter flight.

This paper presents a novel and improved frequency domain identification method for small unmanned helicopters. Compared with the conventional method, this method improves the identification accuracy and reduces the identification error.

This study aims to extend the knowledge in the domain of intellectual capital and entrepreneurship by investigating whether happiness may have a positive influence on entrepreneurial initiative and intellectual property or not.

The used large-scale dataset for 2018 is drawn from the Eurostat. It includes information on individual happiness, sustainability, start-ups, creativity, intellectual property and quality of life, grouped by European countries. Hypotheses are tested through using the linear regression method.

The findings confirm that happiness, along with creativity, fosters both entrepreneurial initiative and intellectual property.

Future studies should test the model by extending the analysis to different world regions and by considering further variables, such as country culture.

The study suggests that policy makers have to focus on improving life conditions and sustainability as a means to foster local economies and communities.

This cutting-edge study is unique in its genus, because the prior literature never focused on these topics jointly. At an academic level, it ties happiness to creativity and to “the entrepreneurial spirit”, thus opening up to a new and vast domain of researches.

The purpose of this paper is to implement the strategies selection process in a proposed formulated mathematical framework to prioritize selected strategies with the interaction of other groups of strategies, known as the strategies interaction model (SIM).

SWOT analysis is a popular useful strategic planning tool, which analyzes organizations internal and external factors. The traditional SWOT procedure lists internal and external factors and derives four groups of strategies based on the organization’s strategic position. SWOT is easy to use as a business analyzing tool, while it is not competent enough for strategic formulation. With the emergence of the economy’s vicissitudes, undulations in the markets and multiple changes, and various variables in the industrial competitive environment, selection of the organization strategies confront uncertainty in decision making. The SIM framework presents a solution to select alternative strategies for organizations in unpredictable situations.

The findings show that SIM is a reliable approach to evaluate, select and rank organization’ strategies. SIM proposes alternative strategies due to the uncertainty of the organization’ environment with respect to the four strategic positions. The SIM’ proposed ranking process is in accordance with the highest impact of each strategy on each other. Furthermore, it possesses advantages of AHP, ANP and other applied multiple criteria decision-making (MCDM) techniques in SWOT analysis.

In this paper SIM is applied within a dairy company located in the north of Iran.

SIM has the advantages of the classic SWOT and fills the gaps of MCDM methods application in the SWOT analysis. Moreover, it provides a formulated algorithm for the organizations to face the uncertainty of the environment. SIM philosophy can be widely used in the decision and managerial implications.

In this study, AlCoCrFeNi–Cu (Cu-based) and AlCoCrFeNi–Ti (Ti-based) high entropy alloys (HEAs) were fabricated using a direct blown powder technique via laser additive manufacturing on an A301 steel baseplate for aerospace applications. The purpose of this research is to investigate the electrical resistivity and oxidation behavior of the as-built copper (Cu)- and titanium (Ti)-based alloys and to understand the alloying effect, the HEAs core effects and the influence of laser parameters on the physical properties of the alloys.

The as-received AlCoCrFeNiCu and AlCoCrFeNiTi powders were used to fabricate HEA clads on an A301 steel baseplate preheated at 400°C using a 3 kW Rofin Sinar dY044 continuous-wave laser-deposition system fitted with a KUKA robotic arm. The deposits were sectioned using an electric cutting machine and prepared by standard metallographic methods to investigate the electrical and oxidation properties of the alloys.

The results showed that the laser power had the most influence on the physical properties of the alloys. The Ti-based alloy had better resistivity than the Cu-based alloy, whereas the Cu-based alloy had better oxidation residence than the Ti-based alloy which attributed to the compositional alloying effect (Cu, aluminum and nickel) and the orderliness of the lattice, which is significantly associated with the electron transportation; consequently, the more distorted the lattice, the easier the transportation of electrons and the better the properties of the HEAs.

It is evident from the studies that the composition of HEAs and the laser processing parameters are two significant factors that influence the physical properties of laser deposited HEAs for aerospace applications.