本研究同时证明，对领导理论的研究，必须结合相应的情景因素，脱离情景的研究是无效的。

This research proved that the researches of leadership must combine corresponding contextual factors, and the studies which apart away from the situations are invalid.

youdao

树索引结合四叉树和R-树的各自优点，既可以满足较高的存储效率，又避免太多的无效查找，达到较好的查找性能。

QR-Tree index combines the advantage of Quadtree and R-Tree, not only serves the need of high storing efficiency, but also avoid of many invalidation query, in order to achieve good query capability.

youdao

本文结合一起案例，从实证法的角度谈出票行为无效和票据无效的关系问题。

Using a case, this paper analyzes problems related to invalid billing and invalid bills.

youdao