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The purpose of this paper is to experimentally and numerically study the transient hydraulic impact and overall performance during startup accelerating process of mixed-flow pump.

In this study, the impeller rotor vibration characteristics during the starting period under the action of fluid–structure interaction was investigated, which is based on the bidirectional synchronization cooperative solving method for the flow field and impeller structural response of the mixed-flow pump. Experimental transient external characteristic and the transient dimensionless head results were compared with the numerical calculation results, to validate the accuracy of numerical calculation method. Besides, the deformation and dynamic stress distribution of the blade under the stable rotating speed and accelerating condition were studied based on the bidirectional fluid–structure interaction.

The results show that the combined action of complex hydrodynamic environment and impeller centrifugal force in the startup accelerating process makes the deformation and dynamic stress of blade have the rising trend of reciprocating oscillation. At the end of acceleration, the stress and strain appear as transient peak values and the transient effect is nonignorable. The starting acceleration has a great impact on the deformation and dynamic stress of blade, and the maximum deformation near the rim of impeller outlet edge increases 5 per cent above the stable condition. The maximum stress value increases by about 68.7 per cent more than the steady-state condition at the impeller outlet edge near the hub. The quick change of rotating speed makes the vibration problem around the blade tip area more serious, and then it takes the excessive stress concentration and destruction at the blade root.

This study provides basis and reference for the safety operation of pumps during starting period

Outside the US and Europe, to establish a good government requires more than Western-style democracy. Adopting universal suffrage fully from the Western model is no longer a panacea to reach the ultimate goal of good governance in the East, i.e., to keep promoting socio-economic renovation can be noted as a prerequisite to have further meaningful political advancement in an Asian polity. The purpose of this paper is to explain how to establish a good but authoritarian government in the East.

Given the good of comparative historical analysis, Lee Kuan Yew in Singapore and Deng Xiaoping in China are selected as both cases for “method of agreement.” Further including “argument based on the contrary” to form a context for macro-historical analysis, this paper outlines two characteristics of the duo’s authoritarian leadership, namely, Ideologies and Policy-making; and Political Modernization, and hence provides a more balanced reevaluation of their governance.

Apart from noting how these two Asian giants more or less contributed to their good but authoritarian governments for long in the twentieth century, such a word of authoritarianism to the duo was quite positive to help legitimize their governance, which was far different from many negative views of the Western world.

As theories put forward by Western academics could not entirely justify modernization among Asian societies in the twentieth century, this paper attempts to answer one question: Does the meaning of authoritarianism remain unchanged in the discourse of the East and the West?

The structural perspective on China's prospect of democratization has three variants. The first emphasizes the structural requisites for the survival of the authoritarian state. It argues that the conditions, such as the governing capacity of the state and support from the Chinese people that used to sustain the authoritarian state, have deteriorated significantly and the authoritarian state cannot escape a collapse in the near future (Chang, 2001). The second focuses on the structural requisites for democratization. It holds that the rise of the middle class and the emerging spread of education in China will create favorable conditions for the country to head toward democratization (Gilley, 2004). The third stresses the resilience of China's authoritarian regime. It argues that the rise of democratic polity in Europe resulted from the special social structures of the continent in the feudal period. Since China's social structure in its premodern period was quite different, democracy did not become a solution even after the middle class emerged in China. For the same reason, China's political change will be most likely to move toward rule by law rather than democratization in the future (Pan, 2006).