During the Spring and Autumn Period, the agricultural production was highly subject to the seasonal changes with the invention of iron tools, thus forming the concept of Solar Term.

春秋战国以后随着铁制农具的出现，农业生产对季节性的要求更高了，就逐渐形成了节气的概念。

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In overall shape, the J-20 is most similar to the mid-1990s-vintage Russian MiG 1.44 prototype and Lockheed Martin's Joint Advanced Strike Technology concept from roughly the same period.

在整体外观上，J - 20更像是90年代中期的俄制米格1.44原型机，或者是同时期的洛克希德·马丁生产的JAST(联合先进打击技术)概念机。

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The concept rests on the lack of private property as the apartments will be rented for the period from 1 day to 10 years.

考虑到私人财产的不足，公寓的出租期限可从1天增至10年。

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During that post-Katrina period, he became familiar with the concept of federal bailouts when he made the argument for federal funds to help insurance companies shoulder the costs of catastrophic events.

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For executives, the floating school concept provides an opportunity to undertake an intensive study period that will provide them with insights and knowledge unlikely to be found in a traditional lecture theater.

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We also have on-balance volume (OBV) data available for this period even though Joe Granville had not yet come up with the concept.

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