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Two friction models of Fe-Fe and Diamond-like carbon (DLC)-Fe were established by molecular dynamics (MD) method to simulate the friction behavior of traditional fracturing pump plunger and new DLC plunger from atomic scale. This paper aims to investigate the effects of temperature and load on the friction behavior between sealed nitrile butadiene rubber (NBR) and DLC films.

In this study, MD method is used to investigate the friction behavior and mechanism of DLC film on plungers and sealing NBR based on Fe-Fe system and DLC-Fe system.

The results show that the friction coefficient of DLC-Fe system exhibits a downward trend with increasing load and temperature. And even achieve a superlubricity state of 0.005 when the load is 1 GPa. Further research revealed that the low interaction energy between DLC and NBR promoted the proportion of atoms with larger shear strain in NBR matrix and the lower Fe layer in DLC-Fe system to be much lower than that in Fe-Fe system. In addition, the application of DLC film can effectively inhibit the temperature rise of friction interface, but will occur relatively large peak velocity.

In this paper, two MD models were established to simulate the friction behavior between fracturing pump plunger and sealing rubber. Through the analysis of mean square displacement, atomic temperature, velocity and Interaction energy, it can be seen that the application of DLC film has a positive effect on reducing the friction of NBR.

The spatial feature is important for scene saliency detection. Scene-based visual saliency detection methods fail to incorporate 3D scene spatial aspects. This paper aims to propose a cube-based method to improve saliency detection through integrating visual and spatial features in 3D scenes.

In the presented approach, a multiscale cube pyramid is used to organize the 3D image scene and mesh model. Each 3D cube in this pyramid represents a space unit similar to a pixel in the image saliency model multiscale image pyramid. In each 3D cube color, intensity and orientation features are extracted from the image and a quantitative concave–convex descriptor is extracted from the 3D space. A Gaussian filter is then used on this pyramid of cubes with an extended center-surround difference introduced to compute the cube-based 3D scene saliency.

The precision-recall rate and receiver operating characteristic curve is used to evaluate the method and other state-of-art methods. The results show that the method used is better than traditional image-based methods, especially for 3D scenes.

This paper presents a method that improves the image-based visual saliency model.

The purpose of this paper is to provide an introduction to the reverse mergers (RMs) conducted in the Chinese stock market by summarizing the regulatory system, surveying the literature on RMs and analyzing the major characteristics of 161 RM cases.

This paper introduces the characteristics and evolution of the regulatory framework governing RM activity in China. Then the paper reviews relevant academic studies on the RMs in China and other countries. Finally, the paper identifies and discusses the major characteristics of 161 RM cases in the Chinese stock market from 2006 to 2016.

Private companies that go public via RMs in China not only have superior asset quality but also demonstrate good accounting and stock price performance after listing, and these results are unlike those of studies on the quality of RMs in other countries.

This paper is based on a survey of 161 RM cases in China’s stock market, with the major characteristics of the RMs being identified and analyzed. The limitations of previous studies and suggestions for further research are discussed.

This paper suggests that the relative superior performance of RMs in the Chinese stock market is caused by the interplay of market forces and regulatory oversight. The Chinese regulator’s pragmatic and flexible approach plays an important role in formulating regulatory policies that respond to the changing macroeconomic environment and financial markets.

The purpose of this study is to investigate the effect of nano ZrC particles on the mechanical and electrochemical corrosion properties of FeCrAl alloys, providing a beneficial reference basis for the development of high-performance carbide reinforced FeCrAl alloys with good mechanical and corrosion properties in the future.

Nano ZrC reinforced FeCrAl alloys were prepared by mechanical alloying and spark plasma sintering. Phases composition, tensile fractography, corrosion morphology and chemical composition of nano ZrC reinforced FeCrAl alloys were analyzed by X-ray diffraction, scanning electron microscopy and energy dispersive X-ray spectroscopy, respectively. Microhardness and tensile properties of nano ZrC reinforced FeCrAl alloys were investigated by mechanical testing machine and Vickers hardness tester. Electrochemical corrosion properties of nano ZrC reinforced FeCrAl alloys were investigated by electrochemical workstation in 3.5 wt.% NaCl solution.

The results showed that addition of nano ZrC can effectively improve the mechanical and corrosion properties. However, excessive nano ZrC could decrease the mechanical properties and reduce the corrosion resistance. In all the FeCrAl alloys, FeCrAl–0.6 wt.% ZrC alloy exhibits the optimum mechanical properties with an ultimate tensile strength, elongation and hardness of 990.7 MPa, 24.1% and 335.8 HV1, respectively, and FeCrAl–0.2 wt.% ZrC alloy has a lower corrosion potential (−0.179 V) and corrosion current density (2.099 µA/cm2) and larger pitting potential (0.497 V) than other FeCrAl–ZrC alloys, showing a better corrosion resistance.

Adding proper nano ZrC particles can effectively improve the mechanical and corrosion properties, while the excessive nano ZrC is harmful to the mechanical and corrosion properties of FeCrAl alloys, which provides an instruction to develop high-performance FeCrAl cladding materials.

We make use of the Volunteered Geographic Information (VGI) data to extract the total extent of the roads using remote sensing images. VGI data is often provided only as vector data represented by lines and not as full extent. Also, high geolocation accuracy is not guaranteed and it is common to observe misalignment with the target road segments by several pixels on the images. In this work, we use the prior information provided by the VGI and extract the full road extent even if there is significant mis-registration between the VGI and the image. The method consists of image segmentation and traversal of multiple agents along available VGI information. First, we perform image segmentation, and then we traverse through the fragmented road segments using autonomous agents to obtain a complete road map in a semi-automatic way once the seed-points are defined. The road center-line in the VGI guides the process and allows us to discover and extract the full extent of the road network based on the image data. The results demonstrate the validity and good performance of the proposed method for road extraction that reflects the actual road width despite the presence of disturbances such as shadows, cars and trees which shows the efficiency of the fusion of the VGI and satellite images.

Tourists with different cultural backgrounds think and behave differently. Accurately capturing and correctly understanding cultural differences will help tourist destinations in product/service planning, marketing communication and attracting and retaining tourists. This research employs Hofstede's cultural dimensions theory to analyse the variations in destination image perceptions of Chinese-speaking and English-speaking tourists to Xiamen, a prominent tourist attraction in China.

The evaluation utilizes a two-stage approach, incorporating LDA and BERT-BILSTM models. By leveraging text mining, sentiment analysis and t-tests, this research investigates the variations in tourists' perceptions of Xiamen across different cultures.

The results reveal that cultural disparities significantly impact tourists' perceived image of Xiamen, particularly regarding their preferences for renowned tourist destinations and the factors influencing their travel experience.

This research pioneers applying natural language processing methods and machine learning techniques to affirm the substantial differences in the perceptions of tourist destinations among Chinese-speaking and English-speaking tourists based on Hofstede's cultural theory. The findings furnish theoretical insights for destination marketing organizations to target diverse cultural tourists through precise marketing strategies and illuminate the practical application of Hofstede's cultural theory in tourism and hospitality.

This paper comes to the point from the tax competition of local government in investment promotion and capital introduction. This paper aims to empirically examine the internal mechanism of enterprises obtaining land resources from local government and its resulting equity investment increase and economic consequences of overinvestment.

The data of China’s A-share listed companies from 2007 to 2014 were used to test the relationship between the increase in enterprise equity investment and the acquisition of land resources and overinvestment. The descriptive statistics, correlation analysis and least squares linear regression were used to solve the above question.

One of the reasons for the enterprise equity increase is to obtain scarce land resources. The enterprise acquisition for land resources leads to overinvestment. The equity investment increase from obtaining land resources will further stimulate enterprise group to overinvest.

The authors could not get the actual data of land that subsidiaries have obtained directly. In this research, the authors get the data using consolidated statements and subsidiary statements indirectly.

The results make contributions to the influencing factors and economic consequence of the enterprise investment structural deviation.

It provides reference to optimize the “interaction” relationship between government and enterprises.

It identified the “dual-channel” conduction mechanism between land resource acquisition and enterprise overinvestment.

The purpose of this paper is to study a new method with which multi‐walled carbon nanotubes (MWNTs) can be dispersed and aligned in low density polyethylene (LDPE) for improving its mechanical properties.

Dispersion and alignment of MWNTs in LDPE matrix are enhanced by ultrasonic vibration, solution casting and melt mixing and flow moulding method. The properties of the composite are characterised using scanning electron microscopy, tensile testing machine and the Izod impact testing machine.

It is found that MWNTs in LDPE achieve some dispersion and alignment resulting in improvement in LDPE's strength and toughness.

Polymer/CNTs nanocomposites are expected to have good process ability of the polymers and high mechanical and functional properties of the CNTs. Enhancing dispersion and alignment of MWNTs in the polymer matrix will promote and expand the applications and development of polymer/MWNTs nanocomposites.

The method that enhances MWNTs dispersion and alignment in LDPE matrix provides a new way for alignment of other CNTs in polymer matrix.

The purpose of this paper is to reveal the characteristics and evolution path of entrepreneurial university in China, through a case study of Huazhong University of Science and Technology (HUST) which has the reputation of “Chinese miniature of higher education” and in which entrepreneurial practice displays “Chinese characteristics”.

The paper has originated from the ongoing thinking after completion of the author's Doctoral thesis. So, a large number of materials collected during the dissertation research will be used in this case, much of which are first‐hand, from investigations, site visits and interviews. As in the Doctoral thesis, a case study approach is also adopted in this paper.

Through the inspection of HUST, it has been found that its entrepreneurial practice is in full compliance with the criteria of the entrepreneurial university. To some extent, the theory of entrepreneurial university is being revised by the practice of HUST. However, there are some “Chinese characteristics” which should be given special attention, such as university‐run enterprises, government‐pulled triple helix, the tradition of government‐run universities and so on.

The paper will help the policy makers clarify the development situation of entrepreneurial university in China, which involves choosing the transformation paths and future directions, and to achieve a good way of building entrepreneurial university in accordance with China's national conditions. At the same time, it will promote international understanding of the entrepreneurial university in China.