This paper introduces the structural features and functions of JWT-type cab radio signal within hump yard field application of its measure method and maintenance are introduced .

介绍了JWT型 驼峰无线机车信号系统构成特点及功能，讲述了它在现场应用中的 检测方法与维护。

However certain problems still exist such as excessive height of stacking layer in material yard and lack of retaining measure .

但也出现了料 场堆层过高，且未设置任何 拦挡的问题。

With the sharp increase of container throughput most ports are limitations due to the land area and yard operations required so they take a multi-layer stacking measure to adapt to these limitations but it may create many invalid reshuffle and complex operational problems .

随着集装箱吞吐量的急剧增加，许多港口由于受到陆域面积和 堆场运营要求的限制，采取了多层 堆垛以适应上述条件限制，但这也会产生许多无效的翻箱和极其复杂的操作问题。