There was a hole in the center of the target.

在靶子的中心有一个洞。

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The microstructure near the penetrated hole of a 60 steel target was analyzed by launching a navy 37 gun.

发射海37弹道炮对60钢装甲靶板穿孔周围的微观结构进行了研究。

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Based on some rule, the improved GEAR algorithm established multipath from the source node to the target region, at the same time, it can avoid the identical node encountering the same hole again.

改进的GEAR算法从均衡网络流量出发，根据规则建立了从源节点到目标区域的多条路径，并且避免了同一节点重复面临同一路由空洞问题。

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If all goes well, NuSTAR's first target will be the black hole nearest Earth.

WSJ: NASA NuStar Telescope to Hunt for Black Holes

Vickers's advice is that when you've adopted your stance and are ready to putt, gaze calmly and steadily at the hole (or target spot) for about three counts, bring your eyes back to the ball in one count and fix your eyes on the back (or top) of the ball for two counts.

WSJ: Why Scientists Love to Study Golf

This month's update issued patches for 49 vulnerabilities, including one that plugs a hole exploited by Stuxnet, the first-known worm designed to target real-world infrastructure such as power stations, water plants and industrial units.

BBC: Two million US PCs recruited to botnets