The Three Gorges Dam in China is the largest dam ever built. Its impacts on the biodiversity and ecological processes in the region are causing concern to ecologists worldwide. The dam and associated environmental alterations may result in a number of regional changes in terrestrial and aquatic biodiversity, as well as in ecosystem structure and functioning. The dam may also provide a rare opportunity for a grand‐scale experiment in habitat fragmentation, allowing ecologists to develop and test a series of hypotheses concerning the dynamics of biodiversity and biotic communities and their responses to disturbances. Such research can help improve conservation practices, stimulate international collaborations, and promote public education on the environment.

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Piezoceramics are widely‐used in high‐power applications, whereby the material is driven in the vicinity of the resonance frequency with high electric fields. Evaluating material's performance at these conditions requires the consideration of inherent nonlinearity, anisotropy, and differences between individual vibration modes. In this work, the relation between electromechanical properties at large vibration velocity and the utilized vibration mode is investigated for a prototype hard piezoceramic. The nonlinear behavior is determined using a combined three‐stage pulse drive method, which enables the analysis of resonant and antiresonant conditions and the calculation of electromechanical parameters. The deviations of coupling coefficients, compliances, and piezoelectric coefficients at high‐power drive were found to be strongest for the transverse length vibration mode. Differences in the mechanical quality factors were observed only between the planar and transverse length modes, which were rationalized by the different strain distribution profiles and the contribution of different loss tensor components. In addition, the influence of the measurement configuration was investigated and a correction method is proposed. The differences between vibration modes are further confirmed by heat generation measurements under continuous drive, which revealed that the strongest heat generation appears in the radial mode, while transverse and longitudinal length modes show similar temperature increase. Piezoceramics are widely‐used in high‐power applications, whereby the material is driven in the vicinity of the resonance frequency with high electric fields. Evaluating material's performance at these conditions requires the consideration of inherent nonlinearity, anisotropy, and differences between individual vibration modes. In this work, the relation between electromechanical properties at large vibration velocity and the utilized vibration mode is investigated for a prototype hard piezoceramic. The nonlinear behavior is determined using a combined three‐stage pulse drive method, which enables the analysis of resonant and antiresonant conditions and the calculation of electromechanical parameters. The deviations of coupling coefficients, compliances, and piezoelectric coefficients at high‐power drive were found to be strongest for the transverse length vibration mode. Differences in the mechanical quality factors were observed only between the planar and transverse length modes, which were rationalized by the different strain distribution profiles and the contribution of different loss tensor components. In addition, the influence of the measurement configuration was investigated and a correction method is proposed. The differences between vibration modes are further confirmed by heat generation measurements under continuous drive, which revealed that the strongest heat generation appears in the radial mode, while transverse and longitudinal length modes show similar temperature increase.

Our previous study has shown that traveling-wave rotary ultrasonic motors using polymer-based vibrators can work in the same way as conventional motors with metal-based vibrators. It is feasible to enhance the performance, particularly output torques, of polymer-based motors by adjusting several key dimensions of their vibrators. In this study, poly phenylene sulfide, a functional polymer exhibiting low attenuation at ultrasonic frequency, is selected as the vibrating body, which is activated with a piezoelectric ceramic element bonded on its back surface. The optimal thicknesses of the polymer-based motors are higher than those of metal-based motors. When the same voltages were applied, the maximum torques and output powers available with the polymer-based motors were lower than the values of the metal-based motors with the same structures. The reasons for the lower torque were explained on the basis of vibration modes. First, the force factors of the polymer-based vibrators are lower than those of metal-based vibrators owing to the great difference in the mechanical constants between polymers and piezoelectric ceramics. Subsequently, though the force factors of polymer-based vibrators can be slightly enhanced by increasing their thicknesses, the unavoidable radial vibrations become higher and cause undesirable friction loss, which reduces the output torques. Though the polymer-based motors have rotation speeds comparable to those of metal-based motors, their output power are lower due to the low electromechanical coupling factors of the polymer-based vibrators.

With their characteristics of low density and elastic moduli, polymers are promising materials for making ultrasonic motors (USMs) with high energy density. Although it has been believed for a long time that polymers are too lossy to be applied to high-amplitude vibrators, there are several new polymers that exhibit excellent vibration characteristics. First, we measure the damping coefficients of some functional polymers to explore the applicability of polymers as vibrators for USMs. Second, to investigate the vibration characteristics, we fabricate bimorph vibrators using several kinds of polymers that have low attenuation. Third, a bending mode USM is fabricated with a polymer rod and four piezoelectric plates bonded on the rod as a typical example of a USM. Through an experimental investigation of the motor performance, it was found that the polymer-based USMs exhibited higher rotation velocity than the aluminum-based USM under a light preload, although the maximum torque of the polymer-based USMs was smaller than the aluminum-based USM. Among the tested polymers, polyphenylenesulfide was a prospective material for USMs under light preloads because of the high amplitude and lightweight of polyphenylenesulfide.

This paper argues that the re-traditionalisation of 'wishing for dragon children' creates difficulties for China's current education reforms and informs the disquiet expressed by Chinese-Australians about Australian education. We develop this argument around three key propositions. First, we explore Confucianism and the civil service examination system in ancient China to situate the expectation of 'wishing for dragon children' historically. Second, we show that processes of re-traditionalisation exercise considerable vitality in modern China. They were used by Chinese Communist authorities for political control, and they now interrupt the de-traditionalising 'Quality Education' reforms. Third, we show that the re-traditionalisation of diasporic ChineseAustralians is evident in their negotiations with Australian education around their desires for 'dragon children'. Parental 'wishing for dragon children' hinders or deflects China's education reforms and subtly affects education in Australia. How to understand, judge and act on the problems of re-traditionalisation and detraditionalisation remain significant concerns for educational research.

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