Wage Increases, Labor Market Integration, and the Lewisian Turning Point: Evidence from Migrant Workers

Labor and Human Capital,

Migration and Labor Mobility in China

China has witnessed the largest labor migration since the reform and opening up policies were implemented. According to the most recent statistics, the total number of rural to urban migrant workers reached 136 million. Migrants are defined as persons who have left out of township for more than 6 months. The migration flow has propelled the economic and societal transition in China through labor productivity enhancement and social restructuring. Accordingly, the Chinese government has improved the migration policies with increasing migration flow and the changes of labor market situations. This report is organized as follows. Section one briefly introduces when and how the migration started by reviewing the history, size and trend, impacts of migration in China and the vulnerability of migrants. Section two reviews the main migration policy changes in the past three decades. Section three illuminates the Lewisian turning point that marks economic development and transitioning in China. Section four discusses the relevance of China’s experiences to other developing economies in terms of economic development and migration policy changes.Migration in China, Labor mobility, Impact of crisis

Improvement of Speech Perception for Hearing-Impaired Listeners

Hearing impairment is becoming a prevalent health problem affecting 5% of world adult populations. Hearing aids and cochlear implant already play an essential role in helping patients over decades, but there are still several open problems that prevent them from providing the maximum benefits. Financial and discomfort reasons lead to only one of four patients choose to use hearing aids; Cochlear implant users always have trouble in understanding speech in a noisy environment. In this dissertation, we addressed the hearing aids limitations by proposing a new hearing aid signal processing system named Open-source Self-fitting Hearing Aids System (OS SF hearing aids). The proposed hearing aids system adopted the state-of-art digital signal processing technologies, combined with accurate hearing assessment and machine learning based self-fitting algorithm to further improve the speech perception and comfort for hearing aids users. Informal testing with hearing-impaired listeners showed that the testing results from the proposed system had less than 10 dB (by average) difference when compared with those results obtained from clinical audiometer. In addition, Sixteen-channel filter banks with adaptive differential microphone array provides up to six-dB SNR improvement in the noisy environment. Machine-learning based self-fitting algorithm provides more suitable hearing aids settings. To maximize cochlear implant users’ speech understanding in noise, the sequential (S) and parallel (P) coding strategies were proposed by integrating high-rate desynchronized pulse trains (DPT) in the continuous interleaved sampling (CIS) strategy. Ten participants with severe hearing loss participated in the two rounds cochlear implants testing. The testing results showed CIS-DPT-S strategy significantly improved (11%) the speech perception in background noise, while the CIS-DPT-P strategy had a significant improvement in both quiet (7%) and noisy (9%) environment