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In China, farmers employed in non-farm work have become important socio-economic actors, but few studies have examined the farmers' perspective in making their work location choices. Based on "push-pull" migration theory, this paper utilizes sectional data from a 2013 survey of farmers in China's Three Gorges Reservoir area to empirically analyze the factors influencing migrant workers' choice of employment location. The results indicate that 60.46% of laborers have migrated from their home province, whereas 39.54% have remained in their home province. Focusing on personal, household, and community characteristics-in addition to the economic characteristics of the sample counties-multinomial logistic regression models reveal that farmer-laborers' employment location decisions are influenced by their personal capital endowment (age, years of education and social networks), family structure (the number of laborers, elders, children and students), home village characteristics (location, economic development level and the degree of relief of the land) and home county economic development level. Notably, male and female laborers' location decisions reveal a converging trend, and their differences are not pronounced. Per capita arable land area has little influence on location decisions, whereas the educational level of laborers has a significant impact. The results differ significantly from those found in previous studies.

A single stage centrifugal compressor has been designed for industrial use. Adjustable Inlet Guide Vanes (IGVs) and vaned diffusers were equipped to meet the requirement of large flow range, high efficiency and constant shaft speed. Both numerical calculations and experiments were implemented to get the performance of this new designed centrifugal compressor. The influence of adjustable IGVs and vaned diffusers on the stage performance characteristic was examined by numerical method. It is shown that numerical simulation results are close to the measured results and predict the stall limit well. The new centrifugal compressor has a comparatively high efficiency and wide operating range. Moreover, unilateral adjustment of either IGV pre-whirl angle or vaned diffuser stagger angle enables an increase in stable operating range opposed to the stage configuration with no adjustment. The combination of simultaneous adjustment of the IGVs and diffuser vanes can not only provide even wider flow range but also keep high efficiency. The identical working point can be operated at different IGV pre-whirl angles and diffuser stagger angles, hence the optimum adjustment schedule for the specified operating line was dug up to obtain an optimum efficiency. Detailed flow field analysis was performed to validated the suitable simultaneous adjustment combinations.