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An accurate detection of overhead ground wire under open surroundings with varying illumination is the premise of reliable line grasping with the off-line arm when the inspection robot cross obstacle automatically. This paper aims to propose an improved approach which is called adaptive homomorphic filter and supervised learning (AHSL) for overhead ground wire detection.

First, to decrease the influence of the varying illumination caused by the open work environment of the inspection robot, the adaptive homomorphic filter is introduced to compensation the changing illumination. Second, to represent ground wire more effectively and to extract more powerful and discriminative information for building a binary classifier, the global and local features fusion method followed by supervised learning method support vector machine is proposed.

Experiment results on two self-built testing data sets A and B which contain relative older ground wires and relative newer ground wire and on the field ground wires show that the use of the adaptive homomorphic filter and global and local feature fusion method can improve the detection accuracy of the ground wire effectively. The result of the proposed method lays a solid foundation for inspection robot grasping the ground wire by visual servo.

This method AHSL has achieved 80.8 per cent detection accuracy on data set A which contains relative older ground wires and 85.3 per cent detection accuracy on data set B which contains relative newer ground wires, and the field experiment shows that the robot can detect the ground wire accurately. The performance achieved by proposed method is the state of the art under open environment with varying illumination.

The purpose of this paper is to explore the evolving mechanism of urban roadway network. With the consideration of self-organization effect and planning effect during evolution, the authors try to demonstrate the impact of preferential attachment, module scale and module structure on the evolving network model.

The roadway network is built in the form of abstract network by dual approach. By using the evolving model of modular growth, the authors analyze the effects and mechanism of the evolving process. Then through numerical analysis, the impact of evolving effects on urban roadway network topology structure is discussed from the aspects of preferential attachment, module scale and module structure.

The module structure property, small-world property and scale-free property of roadway network can be affected with various degrees by the change of preferential attachment and module scale. However, the impact of module structure on network properties is small, which can be ignored. Therefore, in practice, the self-organization effect and planning effect of evolving network can be reached by changing the preferential attachment and module scale, so as to generate the network structure with specific properties.

Some local events, such as road extensions, road demolition and intersection rebuilding, exist during the evolving process under real-world situation. While those cases have not been considered in preferential attachment. Therefore, researchers are encouraged to take these factors into consideration in further research.

The paper has implications for practice in urban transportation planning and roadway constructions, which can help to guide the planning of urban roadway and to adjust or restore partial network when broken down according to the evolving law.

The impact of preferential attachment, module scale and module structure on the evolving network model is measured. And the relationship between different network properties can be used to build some patterns of network. From this point of view, the development of urban roadway network can be predicted and intervened.

The purpose of this study is to examine the relationships among knowledge attributes (complexity and implicitness), interpersonal distrust, knowledge hiding (KH) and team efficacy and second, to explore a new dimension of KH.

Data for this research were collected from more than 940 employees working in manufacturing, information technology (IT), finance and the purification industry. Structural equation modeling was used to test hypothesized relationships.

First, the research confirmed the existence of bullying hiding behaviors in the knowledge economy era based on “knowledge power.” Second, the findings suggest that knowledge attributes are an important predictor of KH behaviors in organizations. The findings implicate the mediating effect of interpersonal distrust and the moderating role of team efficacy, while team efficacy negatively moderated the relationships between interpersonal distrust with evasive hiding and playing dumb, but positively moderated the relationship between interpersonal distrust with rationalized hiding and bullying hiding.

This is the first study to propose bullying hiding, a behavior that has emerged in organizational knowledge transfer, and it is more detrimental to knowledge sharing than other KH behaviors. The results of research on the different regulating effects of team efficacy on KH behaviors enrich the boundary conditions of KH research.

Understandings of house prices and their interrelationships have undoubtedly drawn a great amount of attention from various market participants. This study aims to investigate the monthly newly-built residential house price indices of seventy Chinese cities during a 10-year period spanning January 2011–December 2020 for understandings of issues related to their interdependence and synchronizations.

Analysis here is facilitated through network analysis together with topological and hierarchical characterizations of price comovements.

This study determines eight sectoral groups of cities whose house price indices are directly connected and the price synchronization within each group is higher than that at the national level, although each shows rather idiosyncratic patterns. Degrees of house price comovements are generally lower starting from 2018 at the national level and for the eight sectoral groups. Similarly, this study finds that the synchronization intensity associated with the house price index of each city generally switches to a lower level starting from early 2019.

Results here should be of use to policy design and analysis aiming at housing market evaluations and monitoring.

The paper aims to provide an integrated system for collaborative maintenance training of complex equipment based on virtual maintenance and immersive virtual reality environment.

An integrated platform for collaborative virtual maintenance operation and training of complex equipment is developed. The simulation supporting platform for collaborative virtual maintenance is designed with the combined hierarchical structure and modularized members to support the interactive communication of heterogeneous data and information. By analyzing the collaboration mode of multi operators, the maintenance task allocation model, maintenance operation model and Extensible Markup Language‐based object information template are presented.

The research finds that the proposed system is an efficient platform for collaborative maintenance training of complex equipment.

Appropriate and efficient maintenance task allocation and collaborative maintenance operation of multi operators can significantly improve the maintenance efficiency of complex equipment.

A collaborative virtual maintenance training system of complex equipment based on immersive virtual reality environment is presented.

This paper aims to adopt the knowledge-based view and social network theory to investigate the relationship between network capability ambidexterity and knowledge creation (KC) in the context of open innovation. It also examines the moderating effects of innovation climate on this relationship.

This paper developed a model including network capability ambidexterity, innovation climate and KC. A total of 463 samples were collected from China to test the model and hypotheses by SEM.

The empirical results indicate that network capability ambidexterity is the crucial antecedent of KC. Specifically, network capability ambidexterity consists of the balanced and combined dimensions that both have significant and positive effects on KC. More importantly, the balanced dimension has a stronger effect on KC than the combined. In addition, an innovation climate positively moderates the effects of network capability ambidexterity and KC.

This study advances a new understanding of how network capability ambidexterity influences KC. Moreover, investigating the relationships should provide fresh insights into network capabilities and KC for practitioners in the open innovation context.

With the rapid development of modern economy and the process of urbanization is faster, a large number of historical relics have been mercilessly destroyed in the urban reconstruction. In order to balance the contradiction between urban development and historical heritage and promote the harmonious development of new and old urban areas, it is necessary to research on the old urban areas from the perspective of historical landscape. Old urban area of Jingdezhen is taken as an example in this paper, the present situation of the reconstruction of the old city in Jingdezhen is analyzed. Then, by using the methodology of urban historical landscape, some specific methods for updating and designing the old urban area reconstruction of Jingdezhen is put forward, such as the elements of spatial form, urban texture, historical and cultural landscape elements, streets and alleys, the Changjiang River, public facilities and landscape sketches, and so on. A new design method of landscape transformation of old urban area is established. As the renewal method of respecting the urban history and cultural heritage is a very intelligent urban renewal model, it is found that the application of urban historical landscape in the old urban city is reasonable and effective, which is based on the development of the old urban area and pursues the coexistence of protection and development.

The purpose of this study is to investigate the effects of nanoadditive lubricants on the vibration and noise characteristics of helical gears compared with conventional lubricants. The experiment aims to analyze whether nanoadditive lubricants can effectively reduce gear vibration and noise under different speeds and loads. It also analyzes the sensitivity of the vibration reduction to load and speed changes. In addition, it compares the axial and radial vibration reduction effects. The goal is to explore the application of nanolubricants for vibration damping and noise reduction in gear transmissions. The results provide a basis for further research on nanolubricant effects under high-speed conditions.

Helical gears of 20CrMnTi were lubricated with conventional oil and nanoadditive oils. An open helical gearbox with spray lubrication was tested under different speeds (200–500 rpm) and loads (20–100 N·m). Gear noise was measured by a sound level meter. Axial and radial vibrations were detected using an M+P VibRunner system and fast Fourier transform analysis. Vibration spectrums under conventional and nanolubrication were compared. Gear tooth surfaces were observed after testing. The experiment aimed to analyze the noise and vibration reduction effects of nanoadditive lubricants on helical gears and the sensitivity to load and speed.

The key findings are that nanoadditive lubricants significantly reduce the axial and radial vibrations of helical gears under low-speed conditions compared with conventional lubricants, with a more pronounced effect on axial vibrations. The vibration reduction is more sensitive to rotational speed than load. At the same load and speed, nanolubrication reduces noise by 2%–5% versus conventional lubrication. Nanoparticles change the friction from sliding to rolling and compensate for meshing errors, leading to smoother vibrations. The nanolubricants alter the gear tooth surfaces and optimize the microtopography. The results provide a basis for exploring nanolubricant effects under high speeds.

The originality and value of this work is the experimental analysis of the effects of nanoadditive lubricants on the vibration and noise characteristics of hard tooth surface helical gears, which has rarely been studied before. The comparative results under different speeds and loads provide new insights into the vibration damping capabilities of nanolubricants in gear transmissions. The findings reveal the higher sensitivity to rotational speed versus load and the differences in axial and radial vibration reduction. The exploration of nanolubricant effects on gear tribological performance and surface interactions provides a valuable reference for further research, especially under higher speed conditions closer to real applications.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-07-2023-0220/

This paper analysed survey data of 715 rice-producing households in China to assess the determinants of adoption of five mutually exclusive soil conservation practices (SCPs) and their impact on rice yield and chemical fertiliser use.

The multinomial endogenous treatment effects model was used to account for selection bias and endogeneity arising from both observed and unobserved heterogeneity.

Farms that adopted SCPs as a package experienced an increase in rice yield and decrease in chemical fertiliser use. Adoption of SCPs as a package led to a 12.0% increase in yield and 15.2% decrease in chemical fertiliser use; these results have policy implications for the non-point source pollution control in the agricultural sector. In contrast, adoption of straw retention only significantly reduced yield by 4.9% and increased chemical fertiliser use by 18.1%.

The authors evaluate and compare multi-type of SCPs, such as straw retention, deep tillage and use of organic fertiliser, separately or in combination, and their impacts on smallholder farmers’ rice yield and chemical fertiliser usage.

The purpose of this study is to measure the mass diffusion coefficient of nitrogen in jet fuel using digital holography interferometry for cost-effective designing and modeling of the aircraft tank inerting system.

The mass diffusion coefficients of N₂ in RP-3 and RP-5 jet fuels were measured by digital holography interferometry at temperatures ranging from 278.15 to 343.15 K. The Arrhenius equation is used to adequately describe the relationship between mass diffusion coefficients and temperature. The viscosities of RP-3 and RP-5 jet fuels were also measured to examine the accuracy of the Stokes–Einstein model in calculating mass diffusion coefficients.

As temperature increases from 278.15 to 343.15 K, the mass diffusion coefficients increase 4.23-fold for N₂ in RP-3 jet fuel and 5.13-fold for N₂ in RP-5 jet fuel. The value of Dµ/T is not constant as the Stokes–Einstein equation expressed, but is a weak linear function of temperature.

A more accurate diffusion model is proposed by fitting the measured Dµ/T with the temperature and calculating the mass diffusion coefficients of N₂ in RP-3 and RP-5 jet fuels within 10 per cent relative deviation.

A measurement system for mass diffusion coefficients of N₂ in RP-3 and RP-5 jet fuels was constructed based on the digital holography interferometry. The mass diffusion coefficient can be expressed by a uniform polynomial function of temperature and viscosity.