This paper proves that the Microwave Polarization Difference Index (MPDI) can be used to indicate the vegetation coverage conditions with the AMSR-E L2A brightness temperature data product.

以amsr - E数据为例，研究证明了微波极化差异指数(MPDI)能够反映地表植被覆盖状况。

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The biggest difference is that index funds operate in the way all mutual funds do, in that they are priced at the close of the trading day based on the net asset value (NAV) of the underlying securities.

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The index measures the difference between employers saying they plan to add jobs and those planning to cut them.

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Liken it to the difference between a no-load index fund and an index ETF.

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