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To solve the obstacle detection problem in robot autonomous obstacle negotiation, this paper aims to propose an obstacle detection system based on elevation maps for three types of obstacles: positive obstacles, negative obstacles and trench obstacles.

The system framework includes mapping, ground segmentation, obstacle clustering and obstacle recognition. The positive obstacle detection is realized by calculating its minimum rectangle bounding boxes, which includes convex hull calculation, minimum area rectangle calculation and bounding box generation. The detection of negative obstacles and trench obstacles is implemented on the basis of information absence in the map, including obstacles discovery method and type confirmation method.

The obstacle detection system has been thoroughly tested in various environments. In the outdoor experiment, with an average speed of 22.2 ms, the system successfully detected obstacles with a 95% success rate, indicating the effectiveness of the detection algorithm. Moreover, the system’s error range for obstacle detection falls between 4% and 6.6%, meeting the necessary requirements for obstacle negotiation in the next stage.

This paper studies how to solve the obstacle detection problem when the robot obstacle negotiation.

The deposition of particles onto a substrate during the cold spraying (CS) process relies on severe plastic deformation, so there are various micro-defects induced by insufficient deformation and severe crushing. To solve the problems, many post-treat techniques have been used to improving the quality by eliminating the micro-defects. This paper aims to help scholars and engineers in this field a better and systematic understand of CS technology by summarizing the post-treatment technologies that have been investigated recently years.

This review summarizes the types of micro-defects and introduces the effect of micro-defects on the properties of CS coating/additive manufactured, illustrates the post-treatment technologies and its effect on the microstructure and performances, and finally outlooks the future development trends of post-treatments for CS.

There are significant discoveries in post-treatment technology to change the performance of cold spray deposits. There are also many limitations for post-treatment methods, including improved performance and limitations of use. Thus, there is still a strong requirement for further improvement. Hybrid post-treatment may be a more ideal method, as it can eliminate more defects than a single method. The proposed ultrasonic impact treatment could be an alternative method, as it can densify and flatten the CS deposits.

It is the first time to reveal the influence factors on the performances of CS deposits from the perspective of microdefects, and proposed corresponding well targeted post-treatment methods, which is more instructive for improving the performances of CS deposits.

Internet celebrities have become key resources for consumers making purchase decisions. An increasing number of internet celebrities have begun to exert their influence by creating self-branded products. This study aims to examine the antecedents of consumer attitudes and purchase intentions towards internet celebrity self-brands by integrating cognitive consistency theory, cue utilisation theory and the literature on brand authenticity and celebrity involvement.

Two sub-samples of different social media brand communities were collected via online surveys of consumers with experience purchasing targeted internet celebrity self-brands. Partial least squares structural equation modelling (PLS-SEM) was used to analyse the data.

The results of the two sub-samples provide convergent evidence that brand–consumer congruence, brand authenticity and internet celebrity involvement have positive correlations with consumer attitudes towards internet celebrity self-brands, which then positively correlate with purchase intentions in both psychological (Sub-sample 1) and social (Sub-sample 2) brand communities.

To the best of the authors’ knowledge, this research is the first to develop a comprehensive model of consumers’ attitudes towards internet celebrity self-brands, which predict purchase intentions. The model is empirically tested in different social media brand communities, and the convergent results show the power of the proposed model. Internet celebrity involvement is proposed as a key driver of brand attitudes, which has received little attention. We conceptualise internet celebrity involvement and develop a scale to measure it. Based on the findings, we propose strategies to improve the marketing effectiveness of internet celebrity self-brands.

This paper aims to conduct an analysis of the influence of both the breadth and depth of outward foreign direct investment (OFDI) undertaken by Chinese high-tech listed companies during the period spanning 2010–2019. The data pertaining to these companies was used as a research sample to analyze the effects of OFDI on radical innovation performance.

Hierarchical regression analysis was used to test the proposed models, using survey data collected from 442 high-tech companies in China.

The findings of this study indicate a curvilinear (i.e. U-shaped) relationship between the breadth/depth of OFDI and radical innovation performance. Additional analysis reveals that OFDI plays a role in facilitating innovation breakthroughs by enhancing the internal dynamic capabilities of companies. Moreover, it is observed that a well-established institutional environment in the host country of investment can positively moderate the relationship between OFDI breadth/depth and radical innovation performance.

This study proffers a significant contribution to the understanding of the crucial role played by OFDI from emerging economy companies in enhancing radical innovation performance. Moreover, it offers theoretical guidance for multinational companies aiming to foster innovation breakthroughs.

This study seeks to understand how accountant stereotypes have been constructed and reconstructed at the macro-national and the structural level in Chinese society.

This qualitative investigation into China's social construction of accountant stereotypes employs Becker's (1963) labelling theory. Viewing stereotyping as a socially constructed practice, this study draws on a post-positivistic, reflexive epistemology in conducting 28 semi-structured interviews with accountants and related actors.

Chinese accountant stereotypes are constructed and reconstructed according to the rules created and enforced in different cultural-political periods. The accountant stereotypes constructed during the ancient Confucian period (500 BC – 1948) were replaced during 1949 and 2012 when the political focus shifted towards propagating socialism and later promoting economic growth. They also show how Confucian stereotypes of accountants resurfaced in 2013 but were reconstructed by the central government's cultural confidence policy of propagating Confucianism.

Empirically, prior literature has focused on what the accountant stereotype is and how accountants respond to such stereotypes, but it has neglected the ways in which these accountant stereotypes are politically and culturally constructed, diffused and legitimated. This paper fills in the gap by understanding the social practice of accountant stereotyping in a previously unexplored political-cultural context, namely Chinese society. In theoretical terms, by offering the first use of Becker's (1963) labelling theory in the accounting literature, it furthermore enhances our understanding of how accountants' identities and social standing are shaped by social rules.

Resilience concepts in integrated urban transport refer to the performance of dealing with external shock and the ability to continue to provide transportation services of all modes. A robust transportation resilience is a goal in pursuing transportation sustainability. Under this specified context, while before the perturbations, robustness refers to the degree of the system’s capability of functioning according to its design specifications on integrated modes and routes, redundancy is the degree of duplication of traffic routes and alternative modes to maintain persistency of service in case of perturbations. While after the perturbations, resourcefulness refers to the capacity to identify operational problems in the system, prioritize interventions and mobilize necessary material/ human resources to recover all the routes and modes, rapidity is the speed of complete recovery of all modes and traffic routes in the urban area. These “4R” are the most critical components of urban integrated resilience.

The trends of transportation resilience's connotation, metrics and strategies are summarized from the literature. A framework is introduced on both qualitative characteristics and quantitative metrics of transportation resilience. Using both model-based and mode-free methodologies that measure resilience in attributes, topology and system performance provides a benchmark for evaluating the mechanism of resilience changes during the perturbation. Correspondingly, different pre-perturbation and post-perturbation strategies for enhancing resilience under multi-mode scenarios are reviewed and summarized.

Cyber-physic transportation system (CPS) is a more targeted solution to resilience issues in transportation. A well-designed CPS can be applied to improve transport resilience facing different perturbations. The CPS ensures the independence and integrity of every child element within each functional zone while reacting rapidly.

This paper provides a more comprehensive understanding of transportation resilience in terms of integrated urban transport. The fundamental characteristics and strategies for resilience are summarized and elaborated. As little research has shed light on the resilience concepts in integrated urban transport, the findings from this paper point out the development trend of a resilient transportation system for digital and data-driven management.

Automatic optical inspection (AOI) systems have been widely used in many fields to evaluate the qualities of products at the end of the production line. The purpose of this paper is to propose a local-to-global ensemble learning method for the AOI system based on to inspect integrated circuit (IC) solder joints defects.

In the proposed method, the locally statistically modeling stage and the globally ensemble learning stage are involved to tackle the inspection problem. At the former stage, the improved visual background extraction–based algorithm is used for locally statistically modeling to grasp tiny appearance differences between the IC solder joints to achieve potential defect images for the subsequent stage. At the latter stage, mean unqualified probability is introduced based on a novel ensemble learning, in which an adaptive weighted strategy is proposed for revealing different contributions of the base classifier to the inspection performance.

Experimental results demonstrate that the proposed method achieves better inspection performance with an acceptable inspection time compared with some state-of-the-art methods.

The approach is a promising method for IC solder joint inspection, which can simultaneously grasp the local characteristics of IC solder joints and reveal inherently global relationships between IC solder joints.

The purpose of this paper is to verify the effectiveness of the proposed transient mixed lubrication and wear coupling model [mixed lubrication and wear (MLW) coupling model] under water lubricated conditions by comparing with the experimental results.

Water lubricated bearings are the key parts of the transmission system of an underwater vehicle and some surface ships. In this study, the friction and wear behaviors of rubber, nylon and polyether ether ketone (PEEK) samples with stainless steel underwater lubrication were compared by using ring-block contact structure on multifunctional friction and wear test bench-5000 friction and wear tester.

The results show that the transient wear depth and wear amount of PEEK, nylon and rubber samples under water lubrication are in good agreement with the calculated results of the theoretical model, which verifies the rationality and scientific nature of the MLW coupling model. Thus, the numerical model is applicable for the wear prediction of the journal bearing under water-lubricated conditions. Furthermore, numerical and experimental results reveal that the anti-wear performance among three water-lubricated materials can be ranked by: PEEK > nylon > rubber.

It is expected that this study can provide more information for experimental and numerical research of water-lubricated bearings under water-lubricated conditions.

This study investigates how role overload in the sharing economy leads to emotional exhaustion, which restricts value co-creation activity, and also investigates the moderating effect of perceived platform support.

Two experimental investigations and field research questionnaires were given to respondents with shared mobility industry expertise.

First, role overload detrimentally affects service providers' value co-creation behavior; second, emotional exhaustion acts as a mediator between role overload and value co-creation behavior; and finally, perceived platform support moderates the adverse effect of role overload on emotional exhaustion.

To the best of the authors' knowledge, this study is the first to explore the antecedents of value co-creation behavior from the service provider's perspective, extending the application of COR theory in a sharing economy context.

First, alternative mediators between role overload and emotional exhaustion were not identified. Second, other dimensions of role overload and their impacts were not examined. Lastly, this study did not explore broader perspectives beyond algorithms.

This study recommends that managers reduce role overload ex ante in terms of clarifying responsibilities and obligations, providing substantive resource support and rationalizing order allocation, respectively.

Intumescent coatings are nowadays a dominant passive system used to protect structural materials in case of fire. Due to their reactive swelling behaviour, intumescent coatings are particularly complex materials to be modelled and predicted, which can be extremely useful especially for performance-based fire safety designs. In addition, many parameters influence their performance, and this challenges the definition and quantification of their material properties. Several approaches and models of various complexities are proposed in the literature, and they are reviewed and analysed in a critical literature review.

Analytical, finite-difference and finite-element methods for modelling intumescent coatings are compared, followed by the definition and quantification of the main physical, thermal, and optical properties of intumescent coatings: swelled thickness, thermal conductivity and resistance, density, specific heat capacity, and emissivity/absorptivity.

The study highlights the scarce consideration of key influencing factors on the material properties, and the tendency to simplify the problem into effective thermo-physical properties, such as effective thermal conductivity. As a conclusion, the literature review underlines the lack of homogenisation of modelling approaches and material properties, as well as the need for a universal modelling method that can generally simulate the performance of intumescent coatings, combine the large amount of published experimental data, and reliably produce fire-safe performance-based designs.

Due to their limited applicability, high complexity and little comparability, the presented literature review does not focus on analysing and comparing different multi-component models, constituted of many model-specific input parameters. On the contrary, the presented literature review compares various approaches, models and thermo-physical properties which primarily focusses on solving the heat transfer problem through swelling intumescent systems.

The presented literature review analyses and discusses the various modelling approaches to describe and predict the behaviour of swelling intumescent coatings as fire protection for structural materials. Due to the vast variety of available commercial products and potential testing conditions, these data are rarely compared and combined to achieve an overall understanding on the response of intumescent coatings as fire protection measure. The study highlights the lack of information and homogenisation of various modelling approaches, and it underlines the research needs about several aspects related to the intumescent coating behaviour modelling, also providing some useful suggestions for future studies.