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The purpose of this paper is to resolve the problem of 3D modelling of small objects lacking or without real texture, using an automatic, practical, convenient and effective method.

For each space feature point projected on the surface of the target small object, there are two corresponding 2D points existing. One is an image point in one of the image sequences from the digital camera; another is a point in the slide from the projector. Using the image processing method, the image point can be extracted out accurately so that its 2D coordinates are gained. At the same time, the slide point is designed first so that its 2D coordinates are calculated by the known data. The 3D coordinates of the space feature point can be computed by the space forward intersection.

The projector‐camera system is composed of a slide projector, a digital camera, a control ground, and a computer. The computer controls the other three pieces of equipment, working together automatically and efficiently.

According to the size of the grid, the target object is relatively small. The planar grid is functioned as the calibration of the slide projector and the digital camera.

The paper presents a very effective approach for 3D reconstruction of small objects.

According to the traditional method of the digital camera taking images, the projector is steered so that the projector‐camera system is formed. After being calibrated, respectively, in advance, the projector‐camera system is similar to the binocular vision system in the principle of 3D modelling.

This chapter examines the limit properties of information criteria (such as AIC, BIC, and HQIC) for distinguishing between the unit-root (UR) model and the various kinds of explosive models. The explosive models include the local-to-unit-root model from the explosive side the mildly explosive (ME) model, and the regular explosive model. Initial conditions with different orders of magnitude are considered. Both the OLS estimator and the indirect inference estimator are studied. It is found that BIC and HQIC, but not AIC, consistently select the UR model when data come from the UR model. When data come from the local-to-unit-root model from the explosive side, both BIC and HQIC select the wrong model with probability approaching 1 while AIC has a positive probability of selecting the right model in the limit. When data come from the regular explosive model or from the ME model in the form of 1 + n^α/n with α ∈ (0, 1), all three information criteria consistently select the true model. Indirect inference estimation can increase or decrease the probability for information criteria to select the right model asymptotically relative to OLS, depending on the information criteria and the true model. Simulation results confirm our asymptotic results in finite sample.

The purpose of this paper is to propose a two-degrees-of-freedom wire-driven 4SPS/U rigid‒flexible parallel trunk joint mechanism based on spring, in order to improve the robot’s athletic ability, load capacity and rigidity, and to ensure the coordination of multi-modal motion.

First, based on the rotation transformation matrix and closed-loop constraint equation of the parallel trunk joint mechanism, the mathematical model of its inverse position solution is constructed. Then, the Jacobian matrix of velocity and acceleration is derived by time derivative method. On this basis, the stiffness matrix of the parallel trunk joint mechanism is derived on the basis of the principle of virtual work and combined with the deformation effect of the rope driving pair and the spring elastic restraint pair. Then, the eigenvalue distribution of the stiffness matrix and the global stiffness performance index are used as the stiffness evaluation index of the mechanism. In addition, the performance index of athletic dexterity is analyzed. Finally, the distribution map of kinematic dexterity and stiffness is drawn in the workspace by numerical simulation, and the influence of the introduced spring on the stiffness distribution of the parallel trunk joint mechanism is compared and analyzed. It is concluded that the stiffness in the specific direction of the parallel trunk joint mechanism can be improved, and the stiffness distribution can be improved by adjusting the spring elastic structure parameters of the rope-driven branch chain.

Studies have shown that the wire-driven 4SPS/U rigid‒flexible parallel trunk joint mechanism based on spring has a great kinematic dexterity, load-carrying capacity and stiffness performance.

The soft-mixed structure is not mature, and there are few new materials for the soft-mixed mixture; the rope and the rigid structure are driven together with a large amount of friction and hindrance factors, etc.

It ensures that the multi-motion mode hexapod mobile robot can meet the requirement of sufficient different stiffness for different motion postures through the parallel trunk joint mechanism, and it ensures that the multi-motion mode hexapod mobile robot in multi-motion mode can meet the performance requirement of global stiffness change at different pose points of different motion postures through the parallel trunk joint mechanism.

The trunk structure is a very critical mechanism for animals. Animals in the movement to achieve smooth climbing, overturning and other different postures, such as centipede, starfish, giant salamander and other multi-legged animals, not only rely on the unique leg mechanism, but also must have a unique trunk joint mechanism. Based on the cooperation of these two mechanisms, the animal can achieve a stable, flexible and flexible variety of motion characteristics. Therefore, the trunk joint mechanism has an important significance for the coordinated movement of the whole body of the multi-sport mode mobile robot (Huang Hu-lin, 2016).

In this paper, based on the idea of combining rigid parallel mechanism with wire-driven mechanism, a trunk mechanism is designed, which is composed of four spring-based wire-driven 4SPS/U rigid‒flexible parallel trunk joint mechanism in series. Its spring-based wire-driven 4SPS/U rigid‒flexible parallel trunk joint mechanism can make the multi-motion mode mobile robot have better load capacity, mobility and stiffness performance (Qi-zhi et al., 2018; Cong-hao et al., 2018), thus improving the environmental adaptability and reliability of the multi-motion mode mobile robot.

The objective is to address financing challenges with an innovative technical approach and provide financial support to facilitate the sustainable development of characteristic tourist towns.

In this study, a novel decision model is proposed, which utilizes the CRITIC improved G1 weighting method to analyze financing factors and applies GRA to enhance the TOPSIS model under a Z-Number fuzzy environment. Finally, sensitivity analysis and comparative assessment were conducted to validate the findings and the model.

The findings indicate that equity financing is the optimal mode of financing for characteristic tourist towns, with bond financing serving as a viable alternative. Key factors influencing financing include economic benefit, social benefit and policy risk. Managers should carefully consider these factors when selecting financing methods in order to enhance efficiency and mitigate risks.

As a new business model and value creation method of cultural and tourism integration, the financing decision of a characteristic tourism town has always been the key to the overall promotion and operation. The research constructs a financing index system for characteristic tourism towns based on benefit and risk considerations, using the hot spring town in Anhui Province, China, as a case study to evaluate eight financing models.

From the sixteenth to eighteenth century, China underwent a commercial revolution similar to the one in contemporaneous Europe. The rise of market did foster the rise of a nascent bourgeois and the concomitant rise of a liberal, populist version of Confucianism, which advocated a more decentralized and less authoritarian political system in the last few decades of the Ming dynasty (1368–1644). But after the collapse of the Ming Empire and the establishment of the Qing Empire (1644–1911) by the Manchu conquerors, the new rulers designated the late-Ming liberal ideologies as heretics, and they resurrected the most conservative form of Confucianism as the political orthodoxy. Under the principle of filial piety given by this orthodoxy, the whole empire was imagined as a fictitious family with the emperor as the grand patriarch and the civil bureaucrats and subjects as children or grandchildren. Under the highly centralized administrative and communicative apparatus of the Qing state, this ideology of the fictitious patrimonial state penetrated into the lowest level of the society. The subsequent paternalist, authoritarian, and moralizing politics of the Qing state contributed to China’s nontransition to capitalism despite its advanced market economy, and helped explain the peculiar form and trajectory of China’s popular contention in the eighteenth century. I also argue that this tradition of fictitious patrimonial politics continued to shape the state-making processes in twentieth-century China and beyond.

This study aims to find a dynamic model in an effort to optimize tourism performance in ecotourism destinations. The model structure is built based on competitive performance in geographic areas and the application of ecotourism elements that are integrated with big data innovation through artificial intelligence technology.

Data analysis is performed through dynamic system modeling. Simulations are carried out in three models: First, existing simulation models. Second, Scenario 1 is carried out by utilizing a causal loop through innovation of big data-based artificial intelligence technology to ecotourism elements. Third, Scenario 2 is carried out by utilizing a causal loop through big data-based artificial intelligence technology on aspects of ecotourism elements and destination competitiveness.

This study provides empirical insight into the competitiveness performance of destinations and the performance of implementing ecotourism elements if integrated with big data innovations that will be able to massively demonstrate the growth of sustainable tourism performance.

This study does not use a primary database, but uses secondary data from official sources that can be accessed by the public.

The paper includes implications for the development of intelligent technology based on big data and also requires policy innovation.

Sustainable tourism development.

This study finds the expansion of new theory competitiveness of ecotourism destinations.

This paper aims to present a comprehensive review in major research areas of unmanned air vehicles (UAVs) navigation, i.e. three degree-of-freedom (3D) path planning, routing algorithm and routing protocols. The paper is further aimed to provide a meaningful comparison among these algorithms and methods and also intend to find the best ones for a particular application.

The major UAV navigation research areas are further classified into different categories based on methods and models. Each category is discussed in detail with updated research work done in that very domain. Performance evaluation criteria are defined separately for each category. Based on these criteria and research challenges, research questions are also proposed in this work and answered in discussion according to the presented literature review.

The research has found that conventional and node-based algorithms are a popular choice for path planning. Similarly, the graph-based methods are preferred for route planning and hybrid routing protocols are proved better in providing performance. The research has also found promising areas for future research directions, i.e. critical link method for UAV path planning and queuing theory as a routing algorithm for large UAV networks.

The proposed work is a first attempt to provide a comprehensive study on all research aspects of UAV navigation. In addition, a comparison of these methods, algorithms and techniques based on standard performance criteria is also presented the very first time.

The understanding of the motives for consumers’ support of business underdogs is generally limited. The purpose of this paper is to help address this important research topic by conceptualizing underdog affection as a theoretical construct capturing the emotional attachment held by some consumers toward underdog business entities and advances two perspectives (self- and other-oriented) to unravel its motivational underpinnings.

To test the conceptual model, a survey study was conducted involving 365 respondents drawn from an electronic alumni association list from a medium-sized Midwestern university in the USA. Exploratory factor analysis and confirmatory factor analyses were used to validate the scales, and the structural equations modeling method was used to test the hypothesized effects.

The data support most of the hypotheses (eight out of nine). Under the self-oriented perspective, commerce underdog affection is positively influenced by underdog orientation, need for uniqueness, nostalgia proneness, and hope, and is negatively impacted by their materialism level. Only hope did not impact consumer underdog affection. Under the other-oriented perspective, balance maintenance, top dog antipathy, and empathic concern positively influence underdog affection. The other-oriented factors, especially top dog antipathy and balance maintenance, show stronger effects on commerce underdog affection than self-oriented factors.

The sample was geographically restrictive in the sense that it measured only one group of respondents in the USA. The conceptual model is limited in terms of its coverage of the consequences of underdog affection. While discriminant validity is established in the scale development phase of the study, relatively close relationships do exist among some of these theoretical constructs.

Given the significant evidence linking consumers’ underdog affection to underdog support in commerce, small locally owned businesses could use underdog positioning advertising to differentiate themselves against national retailers. Due to their tendency to display higher underdog affection in commerce, people with higher levels of balance maintenance, top dog antipathy, underdog orientation, emphatic concern, and nostalgia proneness, and lower levels of materialism can be segmented for marketing purposes.

This research indicates that there are ways in which small business entities and non-profits alike can operate in a business setting that is increasingly more competitive and challenging for underdog entities.

This study integrates the various underdog studies across contexts to examine motives to underdog affection, a construct not yet operationalized in business studies. In addition, hypotheses linking eight specific antecedents to commerce underdog affection, via two theoretical perspectives, are empirically examined to assess relative as well as absolute effects.