Publications by authors named "Junwu Bai"

Numerous modern technologies are reliant on the low-phase noise and exquisite timing stability of microwave signals. Substantial progress has been made in the field of microwave photonics, whereby low-noise microwave signals are generated by the down-conversion of ultrastable optical references using a frequency comb. Such systems, however, are constructed with bulk or fibre optics and are difficult to further reduce in size and power consumption.

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The thermal properties of modified uni-traveling carrier (MUTC) photodiode flip-chip bonded to AlN and diamond are simulated. The thermal impedance of InGaAs is the primary source of internal heating. An n-down epitaxial structure is designed to improve thermal dissipation.

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Tidal variations make the water bodies in satellite remote sensing images on different shooting dates have different inundation ranges and depths. Although the underwater substrates do not change, the spectral properties differ due to attenuation effects. These differences have an impact on the results when multi-temporal remote sensing images are used to analyze seagrasses.

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Current power supply networks across the world are mostly based on three-phase electrical systems as an efficient and economical way for generation, transmission and distribution of electricity. Now, many electrically driven devices are relying on direct current or single-phase alternating current power supply that complicates utilization of three-phase power supply by requiring additional elements and costly switching mechanisms in the circuits. For example, light-emitting devices, which are now widely used for displays, solid-state lighting etc.

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Solution-processable electrochromic polymers (ECPs) with high performance are urgently needed for extensive applications. Nevertheless, they suffer from slow switching speed because of low ionic conductivities. Herein, we present an effective strategy to improve the contrast and switching speed in ECPs via facile side-chain engineering.

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Sanshan island of Taihu Lake National Wetland Park in Suzhou was taken as a case study to explore the relationship between land use types and water quality under different spatial and temporal conditions.Firstly,principal component analysis was used to calculate the comprehensive index of water quality for a given sampling site.Secondly,landscape development intensity index (LDI),which can represent combined effects of land use types,was calculated based on GIS spatial analysis technology.

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