So far, this trip partly resembles the Inception phase of an iterative development project: it's common to have a few release-defining (primary) features and several secondary or nice-to-do features.

迄今为止，这一旅行部分类似于迭代开发项目的初始(Inception)阶段：有一些版本定义的(主要的)特性和若干次要的或看是去很好的特性是很普通的。

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In addition, Mr. Abdulmutallab's cash purchase of a round-trip ticket didn't trigger any secondary screening, calling into question the efficacy of the system that is supposed to spot passengers who are acting suspiciously and may be threats.

WSJ: The Middle Seat | How to Improve Travel in 2010

As a secondary revenue stream, Golden Spike also intends to make money from media licensing on each trip.

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