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To take the advantages of terrain-adaptive capability of legged platform and fast-moving ability of wheeled platform, this paper aims to design a leg-wheel mobile platform for obstacle surmounting and analyze the feasibility and locomotivity of different moving modes.

The platform consists of six leg-wheel units. Each of the units has a close-chain mechanical leg and an actuated wheel at the end of the leg. The platform moves with two modes: legged mode and leg-wheel composite mode. The legged mode achieves high mobility driven by crank motors, while the leg-wheel composite mode achieves obstacle-surmounting ability actuated by crank motors and pitch link motors and obtains high efficiency with the hub motors. The gait planning in different modes has been carried out and the obstacle-surmounting capacity has been analyzed.

Based on the results of kinematic analysis and gait planning of the close-chain leg-wheel platform, the high mobility and efficiency obstacle-surmounting ability are demonstrated with the two movement modes. The feasibility of the design and the performance of the mobile platform is verified with the prototype experiment. The results of this paper show that the platform possesses good obstacle-surmounting capability.

The work presented in this paper is a novel exploration to design a close-chain leg mechanism and with an actuated wheel in series. The close-chain leg mechanism has the advantages of high leg lift and single degree of freedom characteristics, which makes the platform obtain the ability of obstacle-surmounting.

The purpose of this paper is to propose an overall deformation rolling mechanism based on double four-link mechanism. The double quadrilateral mobile mechanism (DQMM) has two switchable working modes which can be used to traverse different terrains or climb over obstacles.

The main body of the DQMM is composed of a double four-link mechanism which sharing a public link and two symmetrical steering platforms which placed at both ends of the four-link mechanism. The steering platforms give the DQMM not only steering ability but also reconnaissance ability which can be achieved by carrying sensors such as cameras on steering platforms. By controlling the deformation of the DQMM, it can switch between two working modes (tracked rolling mode and obstacle-climbing mode) to achieve the functions of rolling and obstacle-climbing. Dynamic simulation model was established to verify the feasibility.

Based on the kinematics analysis and simulation results of the DQMM, its moving function is realized by the tracked rolling mode, and the obstacle-climbing mode is used to climb over obstacles in structured terrains such as continuous stairs. The feasibility of the two working modes is verified on a physical prototype.

The work of this paper is a new exploration of applying “overall closed moving linkages mechanism” to the area of small mobile mechanisms. The adaptability of different terrains and the ability of obstacle-climbing are improved by the combination of multi-modes.

The purpose of this paper is to analyze the demands of the core stakeholders and how these stakeholders drive the information disclosure behaviors of the enterprise and local government.

Content analysis was conducted. The authors collected and analyzed information disclosure laws and regulations regarding environmental emergencies in China, as well as related media reports and official accident investigation report about the oil pipeline leakage and explosion accident in City Q. The authors divided the whole process of the accident into four stages, i.e., the prodromal stage, acute stage, chronic stage, and resolution stage, and then analyzed the different demands of stakeholders and the different information disclosure behaviors of the enterprise and local government during these four stages.

During the environmental emergency, the enterprise and local government exhibited information disclosure behaviors for their own benefits. There was severe information asymmetry between the enterprise and local government. Local government acted more positively in terms of information disclosure than the enterprise due to the demands of stakeholders. There were significant differences between the driving effects of different stakeholders. The effects of central government and local communities were the strongest, followed by news media and environmental organizations, whereas general public had the weakest impact. In addition, the effects of stakeholders on the information disclosure varied throughout different stages.

This paper considered a Chinese typical case study, thereby providing details of information disclosure behaviors of the enterprise and local government during an environmental emergency, and making comparative analysis on the driving effects on information disclosure by different stakeholders.

Acoustic signals of the underwater targets are susceptible to noise, reverberation, submarine topography and biology, therefore it is difficult to precisely locate underwater targets. This paper proposes a new underwater Hanbury Brown-Twiss (HBT) interference passive localization method. This study aims to achieve precise location of the underwater acoustic targets.

The principle of HBT interference with ultrasensitive detection characteristics in optical measurements was introduced in the field of hydroacoustics. The coherence of the underwater target signal was analyzed using the HBT interference measurement principle, and the corresponding relationship between the signal coherence and target position was obtained. Consequently, an HBT interference localization model was established, and its validity was verified through simulations and experiments.

The effects of different array structures on the localization performance were obtained by simulation analysis, and the simulations confirmed that the HBT method exhibited a higher positioning accuracy than conventional beamforming. In addition, the experimental analysis demonstrated the excellent positioning performance of the HBT method, which verified the feasibility of the proposed method.

This study provides a new method for the passive localization of underwater targets, which may be widely used in the field of oceanic explorations.

The purpose of this study is to investigate the coupling effects of the velocity slip, rarefaction effect and effective viscosity of the gas film on the performance of the aerostatic guideway in micro-scale and improve the analysis precision of the static performance of aerostatic guideway.

The corresponding model of the gas film flow with consideration of the velocity slip, rarefaction effect and effective viscosity of the gas film in micro-scale is proposed. By solving the corresponding model, the bearing capacity and the stiffness of the aerostatic guideway are obtained through the pressure distributions of the air cavity. Through comparing the bearing capacity and the stiffness in different situations, the couple effects of the three factors are analyzed. Finally, the experimental results about the stiffness are obtained and the contrast between the simulation stiffness and the tested stiffness is achieved.

Through comparing the coupling effects of the micro scale factors under different conditions on the performance of the aerostatic guideway, it was found that when comparing the effects of a single factor, the effect of the first-order slip is the largest. When two factors are randomly combined, velocity slip and viscosity of the gas film is the largest, but these coupling effects are less than the effect of considering three factors simultaneously.

It is essential to consider the first-order velocity slip, the flow factor Q and the effective viscosity when analyzing the static performance of the aerostatic guideway in micro-scale. This makes studying the performance of the aerostatic guideway in micro-scale feasible and improves the machine’s accuracy.

The purpose of this article is to understand the current research status and future development trends in the field of numerical simulation on rock mass grouting.

This article first searched the literature database (EI, Web of Science, CNKI, etc.) for keywords related to the numerical simulation of rock mass grouting to obtain the initial literature database. Then, from the initial database, several documents with strong relevance to the numerical simulation theme of rock mass grouting and high citation rate were selected; some documents from the references were selected as supplements, forming the sample database of this review study (a total of 90 articles). Finally, through sorting out the relationship among the literature, this literature review was carried out.

The numerical simulation of rock mass grouting is mainly based on the porous media model and the fractured media model. It has experienced the development process from Newtonian fluid to non-Newtonian fluid, from time-invariant viscosity to time-varying viscosity, and from generalized theoretical model to engineering application model. Based on this, this article summarizes four scientific problems that need to be solved in the future in this research field: the law of grout distribution at the cross fissures, the grout diffusion mechanism under multi-field coupling, more accurate grouting theoretical model and simulation technology with strong engineering applicability.

This research systematically analyzes the current research status and shortcomings of numerical simulation on rock mass grouting, summarizes four key issues in the future development of this research field and provides new ideas for the future research on numerical simulation on rock mass grouting.

Important developments of China's securities markets within the last two years, namely, the Share Reform, the warrant market, the innovative listed open-end funds (and exchange-traded funds), corporate bonds with detachable warrants, exchange-traded asset-backed securities, are described. The discussion focuses on unique, innovative features of these products, as compared to their counterparts available in more mature markets (when applicable), and points to possible future research themes. The proposed rules with regard to stock index futures and credit trading are also discussed.

This study aims to examine how embeddedness influences consultants' information seeking when making decisions within a social network of relationships, and how these social networks evolve throughout the project delivery stages. The study is grounded in social network theory and examines embeddedness from three perspectives: structural (network cohesion), relational (tie strength in terms of friendship and knowledge awareness) and actor prominence.

A social network analysis (SNA) questionnaire was administered to a team of consultants working on a management consultancy project in Shanghai, China. The SNA measures of density, degree centrality and betweenness centrality were used to analyse relationship patterns among project team members, permitting comparison between the networks. Networks were also compared across the three project delivery stages of collect, consider and create.

Structural embeddedness was observed in the active information seeking behaviour among consultancy team members. The moderate network density of the self-organising information seeking networks across the project delivery stages ensures that the team remains connected but avoids information redundancy and overload. Relational embeddedness was evident through the multiplexity of ties among team members with overlapping friendship and information seeking relationships. The knowledge awareness network's sparseness indicates a team of autonomous knowledge workers with distributed expertise. Project managers were the most prominent actors across the three project delivery stages, underlining these actors' relational leadership role.

The study provides a deeper understanding of collaborative decision-making behaviours in dynamic-project environments. Limited attempts have been made to visualise and analyse the relationships involved in small consulting teams. The novelty of the network approach adopted stems from its ability to offer a structural view of the relationship among consultants, thus offering a distinctive and arguably more complete picture of consultancy team dynamics.

The study validates the social network theory of embeddedness in a real-world collaborative decision-making setting and provides a deeper understanding of information seeking behaviours for decision-making in dynamic-project environments. From a project management process viewpoint, the evolving nature of the information seeking network as it changes across the project stages with associated actors' roles was also visualised graphically, offering a distinctive and arguably more complete picture of consultancy team dynamics.

The purpose of this paper is threefold. First, it aims to review East‐West writing system (cross‐script) differences and summarize previous work examining the cross‐script effect on consumer responses. Second, it aims to describe the implications for international marketing and cross‐cultural studies. Third, it seeks to propose specific questions for future research.

First, the paper presents a critical literature review of studies investigating cross‐script differences influencing consumer attitudes, memory, and information processing. Based on the provided integrative analysis, future directions are indicated for areas relying heavily on written communication, such as international marketing communications, internet marketing, international branding, and cross‐cultural consumer research.

Despite the pervasive nature and importance of written language, scant research has addressed differences between East/West consumer responses attributable to native script processing.

The paper is among the first to point out the insufficiency of scholarly studies on written language effects on consumer responses. The findings raise international marketers' awareness of differences in East‐West written language processing in order to effectively target consumers.