双语畅销书《艾伦图灵传》第8章:水银延时线(17)
As he put it in his 1947 elaboration, 'To store the content of an ordinary novel by such means would cost many millions of pounds.'
It was necessary to make a trade-off between cost and speed of access.
他必须要在速度和成本上进行平衡。He agreed with von Neumann, who in the EDVAC report had referred to the future possibility of developing a special 'Iconoscope' or television screen, for storing digits in the form of a pattern of spots.
他同意冯·诺伊曼的想法，即EDVAC报告指出的，未来有可能研制出一种光电摄像管注，可以用于以点阵的形式存储数据。
This he described as 'much the most hopeful scheme, for economy combined with speed.'
图灵认为这基本上是最有希望的方案，因为它兼顾了速度和经济性。But in a prescient paragraph of the ACE report he also suggested an approach more on the home-made, 'least waste of energy' line:
然而，在ACE报告中，还有一个富有预见性的段落，其中图灵提出了另外一个方案，可以将能耗降至最低：It seems probable that a suitable storage system can be developed without involving any new types of tube, using in fact an ordinary cathode ray tube with tin-foil over the screen to act as a signal plate.
合适的存储系统，似乎并不需要任何新型管，只需要普通的阴极射线管，结合屏幕上的锡纸就可以实现。It will be necessary to furbish up the charge pattern from time to time, as it will tend to become dissipated.
但这里需要做一些改进，要不断地刷新电荷分布，因为它会衰减will be necessary to stop the beam from scanning in the refurbishing cycle, switch to the point from which the information required is to be taken, do some scanning there, replace the information removed by the scanning, and return to refurbishing from the point left off.
……还需要能够在刷新周期中，将扫描束停下来，切到需要处理的点，在那里进行扫描或替换，然后再回到先前离开的点处继续刷新。Arrangements must also be made to make sure that refurbishing does not get neglected for too long because of more pressing duties.
还需要进行一些设计，以保证刷新过程不会被大量的读写过程中断太久。None of this involves any fundamental difficulty, but no doubt it will take time to develop.
这些问题都不存在本质上的困难，但是需要一些时间来实现。
