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This paper aims to identify the factors that are constraining technological innovation to support the development of coalbed methane in China.

The analysis applies ideas relating to national and sector systems of innovation to explain why China’s strategies to support research and technological innovation have failed to stimulate the desired progress in coalbed methane production. It also provides a counter-example of the USA that implemented a number of measures in the 1970s that proved very effective.

The deficiencies of China’s research and development strategies in support of coalbed methane development reflect the national and sectoral systems of innovation. They are exacerbated by the structure of the national oil and gas industry. Key constraints include the excessively top-down management of the national R&D agenda, insufficient support for basic research, limited collaboration networks between companies, research institutes and universities and weak mechanisms for diffusion of knowledge. The success of the USA was based on entirely different systems for innovation and in quite a different industrial setting.

The originality of this analysis lies in placing the challenges facing research and innovation for China’s coalbed methane development in the context of the national and sectoral systems for innovation and comparing with the approach and success of the USA.

Slim and dexterous manipulators with long reaches can perform various exploration and inspection tasks in confined spaces. This paper aims to present the development of such a dexterous continuum manipulator for potential applications in the aviation industry.

Benefiting from a newly conceived dual continuum mechanism and the improved actuation scheme, this paper proposes a design of a slim and dexterous continuum manipulator. Kinematics modeling, simulation-based dimension synthesis, structural constructions and system descriptions are elaborated.

Experimental validations show that the constructed prototype possesses the desired dexterity to navigate through confined spaces with its kinematics calibrated and actuation compensation implemented. The continuum manipulator with different deployed tools (e.g. graspers and welding guns) would be able to perform inspections and other tasks at remote locations in constrained environments.

The current construction of the continuum manipulator possesses quite some friction inside its structure. The bending discrepancy caused by friction could accumulate to an obvious level. It is desired to further reduce the friction, even though the actuation compensation had been implemented.

The constructed continuum manipulator could perform inspection and other tasks in confined spaces, acting as an active multi-functional endoscopic platform. Such a device could greatly facilitate routine tasks in the aviation industry, such as guided assembling, inspection and maintenance.

The originality and values of this paper mainly lay on the design, modeling, construction and experimental validations of the slim and dexterous continuum manipulator for the desired mobility and functionality in confined spaces.

Power loss is an important index to evaluate the transmission performance of a gear pair. In some cases, the starved lubrication exists on the gear contact interface. The purpose of this paper is to reveal the mechanical power loss of a helical gear pair under starved lubrication.

A starved thermal-elastohydrodynamic lubrication (EHL) model is proposed to evaluate the tribological properties of a helical gear pair. The numerical result has been validated against the published simulation data. Based on the proposed model, the influence of thermal effect, working conditions, inlet oil-supply layer and surface roughness on the mechanical power loss and lubrication performance has been discussed.

Results show that the thermal effect has a significant effect on the tribological properties of helical gear pair, especially on mechanical power loss. For a specified working condition, there is an optimal oil supply for gear lubrication to obtain the state of full film lubrication. Meanwhile, it reveals that the mechanical power loss increases with the increase of the surface roughness amplitude.

In this paper, a starved thermal-EHL model has been developed for the helical gear pair based on the finite line contact theory. This model can be used to analyze the tribological properties of gear pair from full film lubrication to mixed lubrication. The results can provide the tribological guidance for design of a helical gear pair.

Pick-and-place tasks are common across many industrial sectors, and many rigid-linked robots have been proposed for this application. This paper aims to alternatively present the development of a continuum robot for low-load medium-speed pick-and-place tasks.

An inversion of a previously proposed dual continuum mechanism, as a key design element, was used to realize the horizontal movements of the CurviPicker’s end effector. A flexible shaft was inserted to realize rotation and translation about a vertical axis. The design concept, kinematics, system descriptions and proof-of-concept experimental characterizations are elaborated.

Experimental characterizations show that the CurviPicker can achieve satisfactory accuracy after motion calibration. The CurviPicker is easy to control due to its simple kinematics, while its structural compliance makes it safe to work with, as well as less sensitive to possible target picking position errors to avoid damaging itself or the to-be-picked objects.

The vertical translation of the CurviPicker is currently realized by moving the flexible shaft. Insertion of the flexible shaft introduces possible disturbances. It is desired to explore other form of variations to use structural deformation to realize the vertical translation.

The proposed CurviPicker realizes the Schöenflies motions via a simple structure. Such a robot can be used to increase robot presence and automation in small businesses for low-load medium-speed pick-and-place tasks.

To the best of the authors’ knowledge, the CurviPicker is the first continuum robot designed and constructed for pick-and-place tasks. The originality stems from the concept, kinematics, development and proof-of-concept experimental characterizations of the CurviPicker.

Flooding is China’s most frequent and catastrophic natural hazard, causing extensive damage. The aim of this study is to develop a comprehensive assessment of urban flood risk in the Hubei Province of China, focusing on the following three issues: (1) What are the factors that cause floods? (2) To what extent do these factors affect flood risk management? (3) How to build an effective comprehensive assessment system that can be used to reduce flood risk?

This study combines expert opinion and evidence from the extent literature to identify flood risk indicators across four dimensions: disaster risk, susceptibility, exposure and prevention and mitigation. The Criteria Importance Through Intercriteria Correlation (CRITIC) and the Grey Relational Analysis (RA)-based Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) decision-making approach were applied to calculate the weighting of factors and develop a model of urban flood risk. Then, ArcGIS software visualizes risk levels and spatial distribution in the cities of Hubei Province; uncertainty analysis verified method accuracy.

The results show that there are significant differences in the level of urban flood risk in Hubei Province, with cities such as Tianmen, Qianjiang, Xiantao and Ezhou being at high risk, while cities such as Shiyan, Xiangyang, Shennongjia, Yichang, Wuhan and Huanggang are at lower flood risk.

The innovative method of combining CRITIC-GRA-TOPSIS reduces the presence of subjective bias found in many other flood risk assessment frameworks. Regional data extraction and uncertainty analysis enhance result reliability, supporting long-term decision-making and urban planning. Overall, the methodological approach developed provides an advanced, highly effective and efficient analysis and visualization of flood risk. This study deepens the understanding of flood risk assessment mechanisms and more broadly supports the development of resilient cities.

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.

Over the past decades, the Internet has had a profound impact on tertiary education, with the emergence of a new format of distance education. With the broadband-connected World Wide Web, students can now pursue their learning, whether formal or informal, more comfortably and effectively. Also, the rapidly emerging technologies offer academics and educational institutions much greater choice in their instructional approaches and learning environments.

Micro lectures are considered to be one of the most effective modes in blended learning. This paper examines our practice of integrating micro lectures into our English for Business course, using an exploratory case study approach. The study focuses on four fields: learning content with technology; learning support services; learning management; and students' learning experiences. The findings indicate that the great majority of students were satisfied with micro lecture learning, and that the flippedclassroom based on micro lecture learning resources can optimize the learning process. We believe that it is time to integrate micro lectures into formal learning in both online learning and face-to-face classroom teaching.

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 paper is to examine and explore the factors that drive users to gift through social network services (SNS).

A questionnaire method was applied to collect data from the sample of the WeChat users who have used mini-program. This paper employed the partial least squares method and used SmartPLS2.0 to analysis sample data, which examined the validity as well as reliability of the sample and further tested the hypotheses by the path coefficients.

The empirical results showed that pleasure, social relationship maintenance, convenience and comprehensiveness are significantly related to SNS gifting behavior, and conscientiousness moderates the relationship between intention and behavior in the context of SNS gifting. However, this study cannot find the effect of symbolic representation, impersonality and gift reciprocity motivations.

Theoretically, this study perfects the research of SNS gifting on the lack of exploring characteristics of comprehensiveness. Practically, this paper lends insights on how SNS providers attract users to adopt gifting.

SNS gifting lacks a complete and effective promotion strategy, resulting in a small number of users as well as low profit. Besides, prior studies have focused on tradition gifting and online gifting. Little research talks about gifting on SNS phenomena, and thus it is necessary to perfect the theory of SNS gifting.

In recent years, with the rapid development of the Internet and e-commerce, the online retail business has grown rapidly. E-commerce platforms can track different click data to understand consumer behavior and demand preferences, so as to make better demand forecasts, and strategically share this information with upstream suppliers. When the platform charges a certain fee for the shared data, the suppliers face the question of whether to purchase demand information. This article aims to analyze the influence of price competition and advertising competition on the suppliers' decisions to purchase information and the online platform for data pricing.

By using static game with incomplete information, this paper explores information-sharing strategies of an online platform with two competitive brand suppliers. The authors use Nash game to analyze the suppliers' purchasing information decision and then obtain the optimal information price of the online platform with information-sharing contract.

This paper shows that demand information sharing benefits both the platform and the suppliers. Without information contracts, the online platform is willing to share demand information with at least one supplier. Especially, when the consumer's sensitivity to advertising is larger and the commission fee charged by the online platform is small, the online platforms will share information with only one supplier. Based on the game outcomes between the suppliers, two pricing strategies for information are proposed under which at least one supplier purchases information. If the consumers are less (more) sensitive to advertising competition, pricing strategy of the online platform induces both suppliers (only one supplier) to purchase information.

At present, most of the information-sharing articles are based on the traditional purchase and sale mode. Based on the background of e-commerce, this paper examines the online platform's information-sharing strategies, which has certain innovation. In addition, the results show that the information-sharing strategy of the online platform is affected by both the price and advertising competitiveness, which provides a new expansion and supplement for the information-sharing literature.