LANGUAGE ACTIVITY
Exercise 1. Summarize your knowledge of the Sequence of Tenses. Translate the sentences into Russian.
It is clear that the newest devices of today will become obsolete tomorrow.
The engineers asked if the work could be compressed into 6 days.
We finally realized that we had chosen the worst possible moment to visit the company.
We were told that the Earth revolves round the Sun.
He considered that this problem would be solved in the nearest future.
I was not sure whether this theory could account for these phenomena.
It is known that magnifying power of microscopes is being increased from year to year.
Exercise 2. Put the verbs in brackets into the correct tense form according to the Sequence of Tenses rule.
It is apparent that fiber optics steadily (to replace) copper wire as an appropriate means of communication signal transmission.
He said that fiber optics (to use) light pulses to transmit information.
The students were told that today more than 80 percent of the world’s long-distance traffic (to be carried) over optical fiber cables.
They read that lenses (to date back) to the burning glasses of antiquity.
She has learnt that revolutionary advances in optics of the 20th century (to begin) with the construction of the first laser.
The Danish astronomer Olaf Roemer calculated that the light (travel) a distance equal to the diameter of the Earth’s orbit around the Sun for about 22 minutes.
In the 19th century none could predict that it (to be possible) to produce images of high-speed events.
Exercise 3. Confirm the expression using Tag Question.
We use electricity to produce heat, … ?
This student made a report at the conference, … ?
The scientists were astonished to discover new stars in the galaxy space, … ?
You were not ready to continue this work, … ?
Many laser physicists have been awarded Nobel Prize, … ?
The experimentalists couldn’t obtain wholly coherent beams of light, … ?
Exercise 4. Change modal verbs of the predicates into their equivalents.
Under the action of light this phenomenon must produce conduction electrons.
In a number of cases, the junction between a metal and a semiconductor or between two semiconductors may have a rectifying action.
Both kinds of conductivity could occur in semiconductors.
4. This energy must be in the form of a photon.
A layer of metal might be made so thin that light easily passes through it.
An electric current can flow when the circuit is closed.
Unit 3
WORD-STUDY
Exercise 1. Check the transcription in the dictionary and read the words listed below.
Boundary, extraneous, coaxial, unique, bandwidth, fidelity, corrode, hazard.
Exercise 2. Choose the proper English equivalents to the Russian words.
Излучение – radiate, radiation, radiative, radiated;
проводить – conductive, conduct, conductance;
приемник – receive, receiver, receiving;
обеспечивать – provide, provider, providing;
первоначальный – original, origin, originally;
передача – transmitter, transmit, transmitting, transmission.
UNDERSTANDING A PRINTED TEXT
List of Terms:
coaxial – коаксиальный кабель
corrode – подвергаться действию коррозии
data rate – скорость передачи информации
duct – соединительная трубка
extraneous signal pickup – прием постороннего сигнала
fidelity – точность, достоверность
fire hazard – угроза пожара
ground loops – замыкание
lash – подсоединять
low-loss glass fiber optic cable – стеклянный оптоволоконный кабель
с низкими потерями
monitor – передавать (информацию)
transmission media – среда, средства передачи информации
optical receiver – оптический приемник
optical transmitter –оптический передатчик
light emitting diode – светодиод
point-to-point fiber optic transmission system – поточечная передающая
оптоволоконная система
power line – силовой кабель (линии электропередачи)
solid-state laser diode – полупроводниковый лазерный диод
spark – возгорание, искровой разряд
splice – сросток, сплетение (проводов)
tap – подключаться
READING AND TRANSLATING THE TEXT
Our current "age of technology" is the result of many brilliant inventions and discoveries, but it is our ability to transmit information, and the media we use to do it, that is perhaps most responsible for its evolution. Progressing from the copper wire of a century ago to today’s fiber optic cable, our increasing ability to transmit more information, more quickly and over longer distances has expanded the boundaries of our technological development in all areas.
Today’s low-loss glass fiber optic cable offers almost unlimited bandwidth and unique advantages over all previously developed transmission media. The basic point-to-point fiber optic transmission system consists of three basic elements: the optical transmitter, the fiber optic cable and the optical receiver.
The optical transmitter converts an electrical analog or digital signal into a corresponding optical signal. The source of the optical signal can be either a light emitting diode, or a solid-state laser diode. The most popular wavelengths of operation for optical transmitters are 850, 1300, or 1550 nanometers.
The fiber optic cable consists of one or more glass fibers, which act as wave-guides for the optical signal. Fiber optic cable is similar to electrical cable in its construction, but provides special protection for the optical fiber within. For systems requiring transmission over distances of many kilometers, or where two or more fiber optic cables must be joined together, an optical splice is commonly used.
The optical receiver converts the optical signal back into a replica of the original electrical signal.
Fiber optic transmission systems – a fiber optic transmitter and receiver, connected by fiber optic cable – offer a wide range of benefits not offered by traditional copper wire or coaxial cable. These include:
1. The ability to carry much more information and deliver it with greater fidelity than either copper wire or coaxial cable.
2. Fiber optic cable can support much higher data rates, and at greater distances, than coaxial cable, making it ideal for transmission of serial digital data.
3. The fiber is totally immune to virtually all kinds of interference, including lightning, and will not conduct electricity. It can therefore come in direct contact with high voltage electrical equipment and power lines. It will not also create ground loops of any kind.
4. As the basic fiber is made of glass, it will not corrode and is unaffected by most chemicals. It can be buried directly in most kinds of soil or exposed to most corrosive atmospheres in chemical plants without significant concern.
5. Since the only carrier in the fiber is light, there is no possibility of a spark from a broken fiber. Even in the most explosive of atmospheres, there is no fire hazard, and no danger of electrical shock to personnel repairing broken fibers.
6. Fiber optic cables are virtually unaffected by outdoor atmospheric conditions, allowing them to be lashed directly to telephone poles or existing electrical cables without concern for extraneous signal pickup.
7. A fiber optic cable, even one that contains many fibers, is usually much smaller and lighter in weight than a wire or coaxial cable with similar information carrying capacity. It is easier to handle and install, and uses less duct space. (It can frequently be installed without ducts.)
8. Fiber optic cable is ideal for secure communications systems because it is very difficult to tap but very easy to monitor. In addition, there is absolutely no electrical radiation from a fiber.
|
