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The purpose of this paper is to explore a novel control approach for swift and accurate positioning and tracking of a mobile robot. Coordinated movement of the mobile robot-body and chameleon-inspired binocular “negative correlation” visual system (CIBNCVS) with neck has rarely been considered in conventional mobile robot design. However, it is vital in swift and accurate positioning and tracking of the target. Consequently, it is valuable to find an optimized method where the robot-body, the biomimetic eyes and neck could achieve optimal coordinated movement.

Based on a wheeled mobile robot, a biomimetic dual Pan–Tilt–Zoom visual system with neck is constructed. The cameras can rely on the unique “negative correlation” mode of chameleon vision, and cooperate with neck, achieving swift search of the 160° scope in front of the robot. Genetic algorithm is used to obtain optimal rotation of the neck and robot-body. Variable resolution targeting is also applied for accurate aiming. Using these two approaches, we can achieve efficient targeting with low energy consumption. Particle filter algorithm is further utilized for real-time tracking.

In the proposed approach, swift and accurate positioning and tracking of the target can be obtained. The rationality of the approach is verified by experiments on flat and sandy terrains with satisfactory results.

This paper proposes a novel control approach for wheeled mobile robots, which achieves coordinated movement of the robot-body and CIBNCVS with neck concerning time and energy saving in the process of swift and accurate tracking.

The purpose of this paper is to find a theoretical reference to adjust the unsymmetrical arc shape and plasma flow of overlapping deposition in wire arc additive manufacturing (WAAM) and ensure the effect of the gas shielding and stable heat and mass transfer in deposition process. The multiphysical numerical simulation and physical experiment are used for validation.

In this study, welding torch tilt deposition and external parallel magnetic field–assisted deposition are presented to adjust the unsymmetrical arc shape and plasma flow of overlapping deposition, and a three-dimensional numerical model is developed to simulate the arc of torch tilt overlapping deposition and external parallel magnetic field–assisted overlapping deposition.

The comparison of simulated results indicate that the angle of welding torch tilt equal to 20° and the magnetic flux density of external transverse magnetic field equal to 0.001 Tesla are capable of balancing the electric arc and shielding gas effectively, respectively. The arc profiles captured by a high-speed camera match well with simulated results.

These studies of this paper can provide a theoretical basis and reference for the calibration and optimization of WAAM process parameters.

The purpose of this paper is to study the influence rules of geometric parameters on deformation of valve slices.

Based on the theory of flexural deformation of elastic thin slice, differential functions of deformation for both single and multi-slices are given and derived in detail. Furthermore, the effects of geometric dimensions on deformation are analyzed particularly by using Matlab/simulink.

The results indicated that the deformation decreases with the increment of fixed ring radius r_a, slice thickness h, and its number n. Meanwhile, the deformation increases with a rise of slice radius r_b, throttle position r_k, the radius ratio λ₁ and thickness ratio λ₂ of slices.

This research can provide some theoretical supports for the parametric and optimal design of adjustable damping shock absorber.

Grey modeling technique is an important element of grey system theory, and academic articles applied to agricultural science research have been published since 1985, proving the broad applicability and effectiveness of the technique from different aspects and providing a new means to solve agricultural science problems. The analysis of the connotation and trend of the application of grey modeling technique in agricultural science research contributes to the enrichment of grey technique and the development of agricultural science in multiple dimensions.

Based on the relevant literature selected from China National Knowledge Infrastructure, the Web of Science, SpiScholar and other databases in the past 37 years (1985–2021), this paper firstly applied the bibliometric method to quantitatively visualize and systematically analyze the trend of publication, productive author, productive institution, and highly cited literature. Then, the literature is combed by the application of different grey modeling techniques in agricultural science research, and the literature research progress is systematically analyzed.

The results show that grey model technology has broad prospects in the field of agricultural science research. Agricultural universities and research institutes are the main research forces in the application of grey model technology in agricultural science research, and have certain inheritance. The application of grey model technology in agricultural science research has wide applicability and precise practicability.

By analyzing and summarizing the application trend of grey model technology in agricultural science research, the research hotspot, research frontier and valuable research directions of grey model technology in agricultural science research can be more clearly grasped.

The purpose of this paper is to summarize the advances in grey system theory research and various application achievements in science and engineering. At the same time, it commemorates the 40th anniversary of the birth of grey system theory and the 10th anniversary of Grey Systems–Theory and Application.

Firstly, the innovations of theoretical research in grey system theory were summarized and some of the widely recognized new results are briefly described. By searching and combing the research results of grey system theory in China national knowledge infrastructure (CNKI) database and Web of Science by Institute for Scientific Information (ISI), this paper shows the rapid development trend of grey system theory in the past 40 years, and the successful applications of grey system theory in the fields of social sciences, natural sciences and engineering technologies.

More than 227 thousands literature were found by input 10 phrases such as grey system, grey number and sequence operator etc. in CNKI database. After entering the new century, the number of grey system papers included in CNKI database is increasing rapidly. Since 2008, more than 10 thousands papers have been included per year and more than 15 thousands papers have been included per year since 2014. Grey system method and model are widely used in physics, chemistry, biology and other fields of natural science, as well as transportation, electric power, machinery and other fields of engineering technology, and a large number of valuable results have been achieved.

It can be seen that the grey system theory plays an important role in promoting China’s scientific and technological progress, innovation and development and high-level talent training from tens of thousands of literatures marked with important national science and technology projects and a large number of grey system literatures published by China’s double first-class universities and double first-class discipline construction universities.

Both innovations of theoretical research and practical application play important role in the growth of new theory. The innovations of theoretical research provide methods and tools for practical application, which is conducive to improve application efficiency and broaden application fields. A large number of practical applications needs have become the source of theoretical innovation and the solid background for the birth of theoretical innovation achievements.

The purpose of this paper is to propose a modification of the Functional Requirements for Authority Data (FRAD) model to accommodate names in non-Roman languages with diverse writing systems.

The model modifies and clarifies the attributes and relationships regarding non-Roman languages of the current FRAD model, based on the definitions of transliteration, transcription, and Romanization in ISO 5127:2001. The modified model overcomes the problems inherent in the current FRAD model when handling writing systems in non-Roman languages.

The proposed model clearly shows the hierarchy of Controlled Access Points (CAPs). CAPs are either based directly on names or derived from other CAPs. For name or person identification, a CAP and its derivations should be treated as a set. The proposed model also resolves ambiguity in the definition of the word transliteration in the current FRAD model.

By establishing new relationships and amending the attributes of the FRAD model, the proposed model better expresses personal names in non-Roman languages as well as names in western languages. It also organizes complex writing systems of non-Roman languages. The proposed model could lead to an improved format for authority data and will facilitate international sharing of data.

This paper aims to explore the relationship between ethical self-fashioning and citizenship practices in the ongoing revival of “Chinese Traditional Culture” pursued in tandem by the party-state and by private actors in present-day China.

Adopting an anthropological approach, the author draws from three sets of resources: (1) research literature on China’s political history and key texts of early Chinese thought, (2) contemporary state discourses on citizen formation, and (3) participant observation notes and interviews with organizers and followers of the Wu-Wei School (a pseudonym). The author conducts a textual analysis of primary and secondary literature and a critical discourse analysis of the ethnographic data and examines emerging themes.

Firstly, the author identifies a crucial dimension in the historical and cultural roots of Chinese citizenship practices: an enduring conception that binds individual ethical self-improvement with socio-political flourishing. Secondly, examining contemporary state discourses on “citizen quality” and “reviving China’s outstanding traditional culture”, the author showcases how party-state authorities call on individuals to self-reform for national rejuvenation. Thirdly, the author investigates how members of the Wu-Wei School construe their individual pursuits of ethical self-improvement as significant for societal progress.

Based on these findings, the author demonstrates the ways in which autochthonous conceptions of Chinese citizenship give a central place to private acts of self-fashioning. The author argues that the entanglement between individual ethics and citizenship practices constitutes a crucial but largely understudied dimension of Chinese citizenship.