Добавил:
Upload Опубликованный материал нарушает ваши авторские права? Сообщите нам.
Вуз: Предмет: Файл:
Спец пер. часть 1.doc
Скачиваний:
201
Добавлен:
26.03.2015
Размер:
1.69 Mб
Скачать

Т е к с т 5. Apparatus Navigation Support

(1.450)

Possibility of periodical specification of the motion parameters during the flight provided by the satellite navigation system allows to develop the schemes of navigation support for solution of different tasks within the frames of onboard and ground control complexes.

The navigation support scheme of the navigation information users in the onboard control complex is determined by requirements to the accuracy of determination and prediction of the System Control (SC) center of mass motion parameters at the moment of the SC functional tasks solution, conditions of the OTCS navigation determination sessions, programming peculiarities and organization of the functional tasks solution.

Minimal and maximum interval size of the statistical treatment of results of the one-stage navigation determinations and correspondingly, the periodicity of the motion parameters updating in OCC are specified based on the following:

  • necessity of operative planning and organization of solution of the apparatus control functional task during the time period compared with the one flight orbit period;

  • achievement of the required motion parameters accuracy by the beginning of the planned interval for corresponding SC functional tasks;

• possibility to perform the navigation determination sessions subject to discontinuity of the navigation field of the GLONASS system orbital group functioning at the current moment of the SC flight.

Vocabulary

specification – зд.: детализация, уточнение

navigation support – навигационная поддержка

onboard – бортовой

prediction – прогноз

mass motion – движение масс

session – заседание, совещание, сеанс

peculiarity – специфика

treatment – зд.: обработка

specified – фиксированный, заданный

subject to – при условии

discontinuity – без прерывания

Задания

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

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

    3. Определите, есть ли в тексте:

  • термины,

  • эквиваленты,

  • клише,

  • средства когезии,

  • прецизионная лексика.

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

Т е к с т 6. Electric Drives

(1.900)

Electric drive is an industrial system which performs the conversion of electrical energy to mechanical energy or vice versa for running various processes such as: production plants, transportation of people or goods, home appliances, pumps, air compressors, computer disc drives, robots, music or image players, etc.

An electrical drive system uses electrical components. These electrical components contain fewer mechanical wear parts, reducing the need to replace these parts, resulting in lower operating costs for the electric drive system. Electric drive systems are very simple. They consist of an electric storage battery, a speed controller with throttle, and an electric motor.

Characteristics

An electric drive provides electrical retarding and reduces service brake wear. The system also has many operational advantages including the control of wheel slip and slide thus reducing the tyre wears. The system delivers a smoother ride for the operator. The electric drive system enhancements include improved retarding grids, slip control algorithms, the latest in diagnostic and trouble shooting software and silencers.

Applications

The electric drive system is especially designed to suit the propeller or rotor research. Both sting and strut mounts are accommodated. The electric drive system is capable of powering three phase AC (alternating current) motors as large as 75 horsepower. Electric drives are also used in boats and are capable of driving the boats at hull speeds comparable with speeds produced by internal combustion engines. In order to have a boat propeller turn at an efficient slow rotation, a reduction gear is an integral part of the motor. To be able to reverse the motion there is a switch in the throttle that controls a forward or reverse relay that alters the rotation of the motor. They are used in vehicles to give better payload, faster acceleration, improved mobility, and lower fuel consumption.