雙語暢銷書《艾倫圖靈傳》第8章:水銀延時線(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.
他必須要在速度和成本上進行平衡。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.
他同意馮·諾伊曼的想法，即EDVAC報告指出的，未來有可能研製出一種光電攝像管注，可以用於以點陣的形式存儲數據。
This he described as 'much the most hopeful scheme, for economy combined with speed.'
圖靈認爲這基本上是最有希望的方案，因爲它兼顧了速度和經濟性。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報告中，還有一個富有預見性的段落，其中圖靈提出了另外一個方案，可以將能耗降至最低：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.
合適的存儲系統，似乎並不需要任何新型管，只需要普通的陰極射線管，結合屏幕上的錫紙就可以實現。It will be necessary to furbish up the charge pattern from time to time, as it will tend to become dissipated.
但這裏需要做一些改進，要不斷地刷新電荷分佈，因爲它會衰減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.
……還需要能夠在刷新週期中，將掃描束停下來，切到需要處理的點，在那裏進行掃描或替換，然後再回到先前離開的點處繼續刷新。Arrangements must also be made to make sure that refurbishing does not get neglected for too long because of more pressing duties.
還需要進行一些設計，以保證刷新過程不會被大量的讀寫過程中斷太久。None of this involves any fundamental difficulty, but no doubt it will take time to develop.
這些問題都不存在本質上的困難，但是需要一些時間來實現。
