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This study aims to establish the laser links between satellites among large-scale distributed satellite systems; a combined attitude control strategy containing two stages is proposed in this paper.

These two stages are: one is the attitude initial pointing control to change the attitude of satellite pointing to the other satellite based on the position information of each satellite; the other one is the high precision attitude tracking control to scan the uncertainty cone because the initial pointing control accuracy is not enough to establish the laser link. At the initial pointing control stage, a method to determine the target attitude of each satellite is presented based on the position information of each satellite, and the fuzzy adaptive control algorithm is used to control the satellites to its calculated attitude. Then, at the high precision attitude tracking control stage, a strategy for laser link acquisition and scanning the uncertainty cone by the lasers of the spacecraft is proposed, and an angular velocity tracking scanning controller is designed while the convergence of the attitude tracking error is ensured through Lyapunov–Krasovskii theory.

Simulations are conducted to verify the effectiveness of the proposed control algorithm, and the laser link for a large-scale distributed satellite system with super long distance is achieved through a combined attitude control strategy.

A combined attitude control strategy is valid for a large-scale distributed satellite system with super long distance.

A combined attitude control strategy can be used to achieve laser link acquisition for a large-scale distributed satellite system like space gravitational wave detection.

A combined attitude control strategy can provide a way to solve the typical problem that pointing control accuracy is not enough to establish the laser link for a large-scale distributed satellite system.

The primary aim of this study is to resolve a longstanding debate concerning the impact of takeover premiums on post-acquisition performance. Specifically, we aim to examine how acquirers' marketing capabilities and payment methods moderate the relationship between takeover premiums and post-acquisition performance.

This study employs linear regression to examine the relationship between acquirers' marketing capabilities, payment methods, takeover premiums and post-acquisition performance in the Chinese manufacturing industry. Data for the analysis were collected from both mergers and acquisition (M&A) announcements and the China Stock Market & Accounting Research Database (CSMAR), covering 1,169 acquisitions from 2012 to 2021.

The results indicate that acquirers' marketing capabilities moderate the impact of takeover premiums on post-acquisition performance. When acquirers possess strong marketing capabilities, takeover premiums increase post-acquisition performance. Conversely, when acquirers lack strong marketing capabilities, takeover premiums are not significantly related to post-acquisition performance. Additionally, it is noteworthy that takeover premiums show a positive correlation with post-acquisition performance, irrespective of the payment methods employed by acquirers for target firms.

Given that takeover premiums are essential for acquiring resources from target firms, it is crucial to maximize the value of these acquired resources. Our findings suggest that acquirers with weaker marketing capabilities before the deal should consider a more conservative approach to pricing target firms.

To investigate the impact of tax enforcement on (a) debt aggressiveness (DEA) and (b) dynamic adjustment of capital structure in Chinese listed firms.

The authors estimate the target capital structure by employing the different models. This study uses data of Chinese A-share listed firms from year 1998 to 2015.

The study suggests that the greater the intensity of tax enforcement, the more radical the listed companies' debt policy. The macroeconomic status and nature of property rights have significant moderating effect on the positive relationship between tax enforcement and DEA of listed companies. Further, tax enforcement has a significant impact on the dynamic adjustment of capital structure.

Research conclusions are conducive to tax administration departments to understand the economic consequences of tax enforcement and further promote tax administration efficiency. Additionally, listed companies can rationally adjust their capital structure to strengthen tax enforcement.

This research helps extend the influencing factors of corporate debt decision-making and capital structure dynamic adjustment to the level of tax enforcement and provide new evidence on the effects of tax enforcement on corporate capital structure.

With the advance of the Silk Road Initiative proposed by China, it has been a focus of China government to develop strategic emerging industries. The development of strategic emerging industries needs the support of competitive intelligence on many aspects such as strategical planning, policy making, industrial structure adjustment, and technology innovation. However, so far there are few studies toward the competitive intelligence systems for strategic emerging industries. In this article, we focus on a number of issues related to the competitive intelligence for strategic emerging industries in China. First, we conduct a strengths, weaknesses, opportunities, and threats analysis on the situations of strategic emerging industries in China, based on which the necessity of building a competitive intelligence (CI) service system for strategic emerging industries is discussed. Next, the authors present a framework of a CI service system for strategic emerging industries in China. The principles, components, working process, and product forms are deeply described. The CI service system proposed in this article consists of a cooperation network platform, three layered organizations, and three systems, which integrates organizations, information, people, network, and service platforms into an ecosystem to offer competitive intelligence supports for government, industry, and enterprises. Finally, the authors discuss a case study of the proposed CI service system for the new energy automobile industry.

The purpose of this paper is to investigate consumer motivations to boutique hotels in Xiamen, China with the push-pull theory.

The survey for this study was conducted in boutique hotels in Xiamen, China.

The results indicated identified “uniqueness-seeking,” “interpersonal experience,” and “social networking” as the primary push motivations and “decoration & theme” and “site value” as the primary pull motivations.

The study is anticipated to provide the industry practitioners in boutique hotels marketing strategies such as positioning, packaging, and advertising.

The scale of urban land has been expanding because the speed of urban development has increased the population. Thus, certain improvement in planning and construction based on circular economy is required. Industrial resource-based city planning and construction is particularly important based on the aforementioned problems and development background. The development of industrial resource cities in the transformation stage based on the circular economy was considered as the breakthrough point. The development, function, and concept of the new district planning were analyzed in view of the design strategy of the current domestic resource-based urban planning; moreover, the planning principles (integration of regional and harmonious resource constructions and coordinated organization function) that are suitable for resource industrial city were presented. In this study, taking the industrial transformation and resource-based city of Yichun as an example, the infrastructure and the general situation of the new district planning in the future were deeply analyzed. In the light of the functional development and planning structure of the transformation and development planning of resource-based industrial cities, the following planning and development strategies were proposed: the centralized small-scale space should be constructed. Diversion control should be carried out on bicycle lane and motorized lane in new area. The three-dimensional layout of the grid should be applied to the overall planning of the road, and according to the expressway, main roads, secondary roads and ordinary sections, there must be four kinds of traffic system, so as to construct a diversified traffic diversion system. The original industrial land should be extended into a continuous space, and the allocation of new district resources after transformation must be suitable for the development plan of brand strategy, so as to perfect the forestry land of Sun Yue gorge street and transform it into RBD recreational and entertainment community, and build a friendly eco city.

The purpose of this paper is to detect edge of image in high noise level, suffering Gaussian noise.

Canny edge detection algorithm performs poorly when applied to highly distorted images suffering from Gaussian noise. In Canny algorithm, 2D‐gaussian function is used to remove noise and preserve edge. In high noise level, 2D‐gaussian function cannot meet the needs. In this paper, an improving Canny edge detection algorithm is presented. The algorithm presented is based on local linear kernel smoothing, in which local neighborhoods are adapted to the local smoothness of the surface measured by the observed data. The procedure can therefore remove noise correctly in continuity regions of the surface, and preserve discontinuities at the same time.

The statistical model of removing noise and preserving edge can meet the need of edge detection in images highly corrupted by Gaussian noise.

It was found that when the noise ratio is higher than 40 percent, the edge detection algorithm performs poorly.

A very useful method for detecting highly distorted images suffering Gaussian noise.

Since an image can be regarded as a surface of the image intensity function and such a surface has discontinuities at the outlines of objects, this algorithm can be applied directly to detect edge of image in high noise level.

This paper uses a probit model to analyse 100 observations in terms of three hypotheses about the formation of owners’ corporations in high‐density private housing estates in Hong Kong within the context of Mancur Olson’s group theory. The findings do not reject the theory, revealing that it is more likely for an older urban estate with fewer owners to form owners’ corporations. The discussion includes a brief introduction to Olson’s group theory and the development of the probit analysis. Some speculative thoughts about public participation in local level urban management and planning are offered in the conclusion.

The purpose of this paper is to introduce structured light image processing technology into pipeline welding automation projects, and develop a vision‐based pipeline girth‐welding robot. The welding torch can accurately track the weld and complete the omni‐orientation welding automatically.

Weld image processing adopts the base theory including Laplacian of Gaussian filter, neighbourhood mean filter, largest variance threshold segmentation and morphologic, etc. obtains good effect of weld recognition.

The paper uses a vision sensor to achieve the weld character's recognition and extraction, directly control the robot tracking weld to complete automation welding. Compared with the existing pipeline welding devices, it does not need the lay orbit or plot tracking mark, which can shorten the assistant time to improve the productivity.

The research findings can satisfy the need of whole‐directional automation welding for large diameter transportation pipe's circular abutting weld. It fits for the automation welding for the long‐distance transportation pipe of petroleum, natural gas, and water.

Aiming at the character recognition and extract of V‐type weld, the method combining the neighbourhood mean filter algorithm with the largest variance threshold segmentation is proposed to obtain the quick weld image processing speed.

This paper aims to study the impacts of groundwater seepage on artificial freezing process of gravel strata, the temperature field characteristics of the strata, and the strata process, closure time and thickness evolution mechanism of the frozen wall.

In this paper several laboratory model tests were conducted, considering different groundwater seepage rate.

The results show that there is a significant coupling effect between the cold diffusion of artificial freezing pipes and groundwater seepage; when there is no seepage, temperature fields upstream and downstream of the gravel strata are symmetrically distributed, and the thickness of the frozen soil column/frozen wall is consistent during artificial freezing; groundwater seepage causes significant asymmetry in the temperature fields upstream and downstream of the gravel strata, and the greater the seepage rate, the more obvious the asymmetry; the frozen wall closure time increases linearly with the increase in the groundwater seepage rate, and specifically, the time length under seepage rate of 5.00 m d⁻¹ is 3.2 times longer than that under no seepage; due to the erosion from groundwater seepage, the thickness of the upstream frozen wall decreases linearly with the seepage velocity, while that of the downstream frozen wall increases linearly, resulting in a saddle-shaped frozen wall.

The research results are beneficial to the optimum design and risk control of artificial freezing process in gravel strata.