You could have one mapping model for two sources, three mapping models for three sources, six mapping models for four sources — all counting just one direction of models.

你可以使两个资源拥有一个映射模型，三个资源拥有三个映射模型，四个资源拥有六个映射模型——这些都随模型的变化而变化。

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Based on the respective analysis of each model and the comparison analysis of the three models, this paper draws three basic conclusions.

在分别对每个模型进行分析和对三个模型进行比较分析的基础上，文章得出了三个基本结论。

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Stratum is an important idea of three dimension strata model. It plays a key action in instauration of three dimension strata model.

地层作为三维地层模型的一个重要概念，在三维地层模型的建立中起着关键作用。

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This model expands on the Fama-French Three-Factor Model by adding a stock momentum risk factor.

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Gene Fama and Ken French popularized this methodology for investors during the 1990s by introducing the Fama-French Three-Factor Model.

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An engineer makes a three-dimensional model of each piece of equipment before the life-size version is built.

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