Sailboats have many different types of fixed keels, such as full keels (see photo) and fin keels.

帆船有许多种不同类型的固定龙骨，例如全龙骨(见上图)及鳍板。

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Fixed the fin shape, adding the fin thickness is not an effective way to increase the efficiency.

在肋片外形不变的条件下，增加肋片的厚度来提高辐射器的散热性能并不是经济的途径；

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Fixed the fin shape, adding the fin thickness is not an effective way to increase the efficiency.

在肋片外形不变的条件下，增加肋片的厚度来提高辐射器的散热性能并不是经济的途径；

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