Unit 5. Технические тексты т е к с т 1. The Difficulties of Working in Space

(1.500)

"It isn't possible for astronauts to use normal tools from the hardware store, because working in space means doing so in a unique environment," said Jill McGuire, crew aids and tools manager for the Hubble Space Telescope Program at Goddard.

"The astronauts have limited mobility in their space suits, so one of the things they have to cope with is hand fatigue due to constantly fighting against the pressure of the suit," McGuire said. "Therefore, we need to build larger tools, that have specially designed handles and triggers that make it easier for them to work in their suits."

Another hard part of working in the space environment is the large temperature extremes, which create a need for special materials and lubricants that you can't find in a hardware store.

Most tools the average consumer uses contain a "wet" lubricant or oil, which cannot withstand harsh temperature extremes, so the Goddard engineers use a different technique, called "dry film" lubricant, which allows parts to slide with respect to one another.

This isn't to say that commonly used tools are worthless for servicing missions, as special adaptations can sometimes be done to make them fit for use. In fact, much of the hardware in the astronauts' inventory of custom tools are actually modified versions of common tools, such as sockets and socket extender bars. The rest are designed and built to help the space-walking astronauts service the one-of-a-kind interfaces and features on the telescope.

Vocabulary

hardware store – хозяйственный магазин

crew – экипаж

aids and tools – приборы и приспособления

cope – справляться

fatigue – усталость

trigger – защелка, пусковой механизм

lubricant – смазочный материал

average – среднестатистический

harsh – резкий, суровый

slide – скользить

servicing mission – полет для обслуживания на орбите

custom tool – прибор, выполненный на заказ

socket – розетка

extender bar – удлинитель

one-of-a-kind – единственный в своем роде

feature – функция, черта, свойство

Задания

1. Выполните лингво-переводческий анализ текста.

2. Установите, какие части текста представляют собой сооб-щение сведений.

3. Выявите систему языковых средств, оформляющих техни-ческий текст.

4. Определите, есть ли в тексте:

• термины,

• эквиваленты,

• клише,

• средства когезии,

• прецизионная лексика.

5. Выполните письменный перевод текста на русский язык, соблюдая специфику данного жанра.

Т е к с т 2. Transparency of the Water

(2.200)

Water is at best an imperfect medium for transmission of light waves, owing to a greater decrease in intensity with distance from a source than predicted by geometrical considerations, such as the inverse square law for a point source. This attenuation is largely the result of scattering by impurities, and varies tremendously with the amount and nature of such impurities.

If the laws of geometrical image formation hold, all the light which reaches the camera from a given point on an object to be photographed combines at a corresponding image point on the plane of the film. If scattering and absorption occur in the intervening medium, however, part of this light does not reach the camera and, what is worse, light scattered from other geometrical paths does arrive, thus producing a decrease in definition and contrast of the image.

This reduction in visibility is inherent in any given medium, and becomes rapidly more serious as the distance increases, as the attenuation and scattering increase exponentially with the path traversed.

Loss of intensity by absorption and scattering could of course be compensated by using brighter illumination, but the failure of the light to form a good image cannot. An upper limit to possible working distances is therefore set by the clarity of the water, and this limiting factor is an important one for measurements on any scale. In tests on a laboratory scale, such as might be performed in a tank several feet on a side with detonator caps, reasonably clean tap water is often satisfactory, but must be changed when contaminated by dirt, solid carbon explosion products, or growths.

With larger charges, transparency is a more difficult problem because larger working distances are necessary which, in turn require larger volumes of clearer water. If an artificial basin is used, the water must be changed or cleaned periodically, which becomes a considerable expense for work with even a few pounds of explosive. For charges of more than a few pounds, work must almost always be carried out in natural bodies of water, and the clarity of this water is frequently the limiting factor, which makes satisfactory pictures difficult or impossible to obtain.