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Collaborative robots (cobots) are widely used in various manipulation tasks within complex industrial environments. However, the manipulation capabilities of cobot manipulation planning are reduced by task, environment and joint physical constraints, especially in terms of force performance. Existing motion planning methods need to be more effective in addressing these issues. To overcome these challenges, the authors propose a novel method named force manipulability-oriented manipulation planning (FMMP) for cobots.

This method integrates force manipulability into a bidirectional sampling algorithm, thus planning a series of paths with high force manipulability while satisfying constraints. In this paper, the authors use the geometric properties of the force manipulability ellipsoid (FME) to determine appropriate manipulation configurations. First, the authors match the principal axes of FME with the task constraints at the robot’s end effector to determine manipulation poses, ensuring enhanced force generation in the desired direction. Next, the authors use the volume of FME as the cost function for the sampling algorithm, increasing force manipulability and avoiding kinematic singularities.

Through experimental comparisons with existing algorithms, the authors validate the effectiveness and superiority of the proposed method. The results demonstrate that the FMMP significantly improves the force performance of cobots under task, environmental and joint physical constraints.

To improve the force performance of manipulation planning, the FMMP introduces the FME into sampling-based path planning and comprehensively considers task, environment and joint physical constraints. The proposed method performs satisfactorily in experiments, including assembly and in situ measurement.

In any time and space and under any circumstance, we find peasants are never passive actors in their livelihoods and rural development. Instead, they always create space for manoeuvre in order to make changes. This chapter analyses the innovative actions taken by the majority of rural inhabitants in rural areas during the overwhelming modernization process, so as to affirm that peasants are the main actors of rural development. It is they who have shaped the transformation of rural societies and the history. Through the analysis, this chapter concludes that rural development is not an objective, a blueprint nor a design. It is not the to-be-developed rear field in modernization. It is not the babysitter for cities, nor a rehearsal place for bureaucrats to testify their random thoughts. Rural development is what peasants do. The path they have chosen reveals scenery so different from modernization. If we regard development as a social change, or a cross with influential meanings, we could understand rural development as peasants’ victories over their predicament. Villages accommodate not only peasants, but without peasants villages would surely vanish. In this sense, the most important part in rural development or rural change is peasants – their conditions and their feelings.

The purpose of this paper is to study the combined effects of inlet airflow temperature and the expansion angle of the upper expansion surface (upper expansion angle) on the performance of the scramjet nozzle.

The Spalart-Allmaras turbulence two-dimensional model of the nozzle is established for the study. The influence of inlet airflow temperature on the performance of the nozzle is analyzed by detecting the change of the wall pressure of the nozzle. The three angles are chosen for the upper expansion angle (β_b) in the model: 8°, 12° and 16°. The temperature of inlet airflow is 600–1,800 K.

The study results show that when the β_b is 8° and 16°, the wall pressure of the nozzle has a complicated and large fluctuation with the inlet airflow temperature, while the wall pressure has little change as β_b is 12°; the thrust coefficient, pitching moment coefficient and lift coefficient of the nozzle fluctuate greatly with the increase of the inlet airflow temperature when β_b is 8° and 16°, while the thrust coefficient, pitching moment coefficient and lift coefficient have little fluctuation as β_b is 12°.

The study of the combined effects of the inlet airflow temperature and upper expansion angle on the performance of the scramjet nozzle can provide guidance for the design of scramjet nozzles.

As an efficient self-healing intelligent material, the encapsulation-based self-healing resin mineral composite (SHC) has a broad application prospect.

Aiming at the cracking performance of SHC, the dynamic load condition is employed to replace the traditional static load condition, the initial damage of the material is considered and the triggered cracking process and influencing factors of SHC are analyzed based on the extended finite element method (XFEM). In addition, the mechanism of matrix cracking and microcapsule triggered cracking process is explained from the microscopic point of view, and the cracking performance conditions of SHC are studied. On this basis, the response surface regression analysis method is used to obtain a second-order polynomial model of the microcapsule crack initiation stress, the interface bonding strength and the matching relationship between elastic modulus. Therefore, the model could be used to predict the cracking performance parameters of the microcapsule.

The interfacial bonding strength has an essential effect on the triggered cracking of the microcapsule. In order to ensure that the microcapsule can be triggered cracking normally, the design strength should meet the following relationship, that is crack initiation stress of microcapsule wall < crack initiation stress of matrix < interface bonding strength. Moreover, the matching relationship between elastic modulus has a significant influence on the triggered cracking of the microcapsule.

The results provide a theoretical basis for further oriented designing of the cracking performance of microcapsules.

Most of 823,000 ethnic Chinese people are living in Southern Vietnam among distinct dialectical groups. Each maintains its own pantheon of gods; the majority worships standardized Thien Hau. The Hakka in Buu Long are the only group that worships the craft-master gods. This difference creates a challenging gap between the subgroups and reveals the unorthodox nature of the Hakka’s traditions. The purpose of this paper is investigate the continuous efforts to achieve “evolving standardization” and solidarity through the charismatic efforts of the local Hakka elites in Buu Long by their liturgical transformation.

The study further discusses the multilateral interaction and hidden discourses by applying Watson’s (1985) theory of standardization and orthodoxy as well as Weller’s (1987) concept of context-based interpretation.

Truthfully, when facing pressures, the Hakka in Southern Vietnam decided to transform their non-standard worship of the craft masters into a more integrative model, the Thien Hau cult, by superimposing the new cult on the original platform without significant changes in either belief or liturgical practice. The performance shows to be the so-called “the caterpillar’s spirit under a butterfly’s might” case.

The transformation reveals that the Hakka are currently in their endless struggles for identity and integration, even getting engaged in a pseudo-standardization.

This Hakka’s bottom-up evolutionary standardization deserves to be responded academically and practically.

The paper begins with a setting of academic discussions by western writers in this area and then moves on to what makes the practical transformation, how does it happen, and what discourses are hidden underneath.