“跳单”行为亦称为“跳中介”，是指买受人或出卖人已经与中介（公司）签署了预售确认书、委托求购协议或出卖协议，中介公司已经按照协议履行了提供独家资源信息并促使买卖双方见面洽谈等促进交易的义务，买卖一方或双方为了规避或减少按照协议约定履行向中介交付中介费的义务，跳过中介而私自签订买卖合同的行为。
其次，讨论了两跳单中继多载波协同通信系统的信道估计的问题，主要是基于辅助块状导频的方法；
Second, channel estimation algorithms of two-hop OFDM cooperative communication system with single relay are discussed, which are mainly based on block pilot.
孩子们在地上单腿跳来跳去的玩耍。
麦克称，Manet的体系结构包括建立一个路由表，每个节点不仅知道其“单跳”相临节点，还应知道与其他相临节点的下一个节点。
Macker said the Manet architecture involves building a routing table in which each node knows not only its neighbors one hop away but also the nodes next to those neighbors.
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