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ФЕДЕРАЛЬНОЕ АГЕНТСТВО ПО ОБРАЗОВАНИЮ
Государственное образовательное учреждение
высшего профессионального образования
САНКТ-ПЕТЕРБУРГСКИЙ ГОСУДАРСТВЕННЫЙ УНИВЕРСИТЕТ
АЭРОКОСМИЧЕСКОГО ПРИБОРОСТРОЕНИЯ
REALMS OF ENGINEERING
(УЧИСЬ ЧИТАТЬ
НАУЧНО-ТЕХНИЧЕСКУЮ ЛИТЕРАТУРУ)
Методические указания по развитию навыков
профессионально-ориентированного чтения
Санкт–Петербург
2007
Составители: В.О. Перминов, И.И. Громовая
Под редакцией канд. филол. наук доц. В.О. Перминова
Рецензенты: Д.С. Исаева, О.В. Злобина
В системе массовой коммуникации и познания чтение
выступает как индивидуализированная форма деятельности
человека. Чтение стало важнейшим средством развития
теоретического мышления и способом достижения человеческого
знания.
Указания позволяют раскрыть специфику обучения чтению в
процессе преподавания иностранных языков и предназначены для
студентов 3 курса ведущих специальностей университета.
Основная цель выпуска состоит в совершенствовании
основных навыков речевой деятельности (чтения и говорения).
Подготовлены к публикации кафедрой иностранных языков и
рекомендованы к изданию редакционно-издательским советом
Санкт–Петербургского
государственного
университета
аэрокосмического приборостроения.
© ГОУ ВПО «Санкт-Петербургский
государственный университет
аэрокосмического приборостроения»,
2005
© ГУАП, 2007
Подписано к печати 15.02.05 Формат 60х84 1/16. Бумага офсетная.
Печать офсетная. Усл.печ.л. 2,3 Тираж 500 Заказ № 40
Отпечатано с оригинал-макета, подготовленного автором
Редакционно-издательский центр ГУАП
190000, Санкт-Петербург, ул. Б. Морская, 67
UNIT 1. SOME FUNDAMENTALS OF ELECTRONICS
I. Прочтите и запомните эти слова и словосочетания:
alternating current
переменный ток
direct current
постоянный ток
capacity
емкость, мощность
cell
элемент, ячейка
charge
нагрузка, заряд
circuit
цепь, контур, схема
conductor
проводник
conductivity
удельная проводимость, электропроводимость
device
аппарат, прибор, устройство
frequency
частота
insulator
диэлектрик, изолятор
particle
частица
количество
quantity
источник
source
напряжение
voltage
провод, проволока
wire
II. Определите по суффиксам, к каким частям речи относятся слова,
переведите их:
inventor, invention, development, conductor, conduction, insulator, insulation,
resistor, resistance, transmitter, transmission, achievement, produce,
production.
III. Назовите существительные, от которых образованы следующие
прилагательные. Переведите исходные и производные формы:
-al: experimental; structural; cultural;
-ic: electrostatic; magnetic;
-ical: technological; theoretical;
-ive: positive; negative; primitive;
-ful: powerful; hopeful.
IV. Образуйте от известных вам слов существительные,
прилагательные, наречия с помощью указанных суффиксов. Переведите
исходные
и
производные
формы:
1
a) transform v- ……… –tion n
generate v- ……… –tion n
construct v- ……… -tion n
transform v- ……… -er n
resist v -……… –or n
transmit v -……… -er n
develop v - ……… -ment n
equip v -……… -ment n
b) nucleus (n) n -……… -ar a
line n -……… –ar a
experiment n -……… –al a
structure n - ……… –al a
c) theoretical a -…… –ly adv
technological a -…… -ly adv
positive a -……… -ly adv
negative a -……… -ly adv
V. Переведите, обращая внимание на значение отрицательных
префиксов de-, dis-:
1. to code - to decode; 2. to form - to deform; 3. to compose - to decompose; 4.
to increase - to decrease; 5. to charge - to discharge; 6. to connect - to
disconnect.
VI. Переведите, обращая внимание на значение отрицательного
префикса un-:
1. usable - unusable; 2. successful - unsuccessful; 3. reliable - unreliable; 4.
balanced - unbalanced; 5. desirable - undesirable; 6. changed - unchanged; 7.
achievable - unachievable; 8. accomplished – unaccomplished.
VII. Прочтите и переведите текст. Ответьте на следующий вопрос:
Is the text intended for students, specialists, or general readers?
WHAT IS ELECTRONICS?
Electronics is the field of science and engineering. It deals with the
conduction of electricity in electron devices. For example, conduction through
a vacuum is carried out by parts of atoms that are known as electrons.
Electricity is a movement of electrons. The electron is a very small charge
of electricity. This charge is negative. Electronic conductors contain free
electrons that are able to move from atom to atom. Thus, electrons are able to
form an electric current through a conductor. The electrons flow through the
conductor when all its parts are of the same potential.
Electronics deals with the conduction of electricity in electron devices. The
electron device is a device in which conduction by electrons occurs through a
vacuum, gas or semiconductor. In electronic devices, the electric current can
flow in one direction only. The diode is the simplest form of a vacuum tube
2
which contains two electrodes. One of these electrodes is the cathode which is
the primary source of electron emission. If a battery of proper voltage is
connected to the terminals of the cathode, the wire is heated and electrons
begin to move. When the temperature of the cathode rises, these electrons will
flow from the cathode to the anode. Thus electronics deals with the sources
and movements of electrons through tubes, metals and other conductors. In
general, metals are better conductors than non-metals. In order to maintain a
steady flow of electrons through a conductor, a constant electrical pressure
must be applied. This pressure is known in the field of electronics as voltage
and is measured in volts. Voltage is not a measure of quantity. It is the
difference in potential that may exist between external terminals of a
conductor. The terms voltage, potential and potential difference may be used
instead of each other.
It has been shown that electricity is a movement of electrons through a
vacuum, a gas or metals. Thus, the field which includes electricity has been
known as the field of electronics.
On the other hand, in order to study electronics, it is necessary to know the
action of the electron. It has been known that the electron is a part of an atom.
Under certain conditions it may behave as if it were able to have the properties
of a very small and light particle of matter. Hence, in order to study electronics
it is necessary to know the principles of electricity.
TYPES OF CURRENT
There are several types of current, although all are essentially the same. For
all practical purposes, they may be considered as alternating or direct current.
DC is known to be a current whose direction remains the same. DC is usually
obtained from DC generators or batteries. Alternating current is known to be a
current the direction of which reverses at fixed intervals. AC can be obtained
by several methods described later. Alternating current varies in intensity from
zero to some positive value, then reduces to zero and rises in intensity to some
negative value before it again reduces to zero.
Electric Current
An electric current is the time rate of flow of electric charge across a
surface. Before discussing the types of an electric current in more detail it
should be mentioned that two types of current were discussed. However, there
are actually three types of current: conduction current (ток проводимости),
convection current (конвекционный ток) and displacement current (ток
смещения). Conduction current is due to the motion of charges in a neutral
3
system, as electrons in a conductor or the motion of electrons and holes in
semiconductors. On the other hand, the convection current, as compared with
the conduction current, is due to the motion of unneutralized charges, as the
motion of electrons in a vacuum tube. The displacement current is an effect of
a charge of an electric flux. Current is a scalar. The current through a specified
surface is given by the integral over that surface of the normal component of
current density. Sometimes it is said that a current has a direction but, actually,
being a scalar, current has a value (plus or minus) but not a direction. The
positive sense of a current is generally taken as the direction in which positive
charges would move if they were the carriers of the current. In metals, where
the current is actually carried by negative electrons, the flow of electrons is
reverse to the positive direction of the current. For example, one coulomb of
negative charge passing to the left per second is one ampere of (positive)
current to the right.
The term "charge of electricity" is defined as follows. If the number of free
electrons in a conductor is above the normal number, the conductor is said to
be negatively charged. If the number is below normal, the charge is called
positive. The amount of an electric charge is determined in terms of quantity,
the coulomb.
It should be pointed out that carrier is the general name given to electrically
charged particles such as: electrons, ions etc.
Electric Conduction
Electronics deals with conduction of electricity through a vacuum, gas or
semiconductors. From the point of view of the present theory, electric
conduction is the transfer of electricity due to the motion of electric charge.
The flow of charge per unit time is the electrical current.
Under certain conditions, all forms of matter can conduct electricity to
some degree. For most purposes, materials used in electronic engineering are
considered as conductors and insulators. According to the present theory, a
conductor is considered to be a material in which free electrons and/or ions are
able to move under the influence of an electric field, and thus to produce the
phenomenon known as an electric current. A conductor must, therefore, exist
in a state of at least partial ionization. In order to function as a good conductor,
the material should allow the movement of electrons with ease, to function as a
good insulator the material should oppose the movement of electrons, because
an insulator is, in general, a non-conductor of electricity.
It has been already shown that the electron is a part of an atom. It has the
smallest possible charge of negative electricity.
4
In general, metals are better conductors than nonmetals. In most metals, the
moving charges are electrons. There is, however, a large number of materials
conductivity of which is intermediate between conductors and insulators.
These materials are referred to as "semiconductors".
PRINCIPLES OF ELECTRON EMISSION
It has been shown that electronics deals with sources and movements of
electrons through tubes, metals, and other conductors. Thus, it deals with the
emission and flow of electrons. Any electron flow is the flow of free electrons.
The electron emission is the liberation of electrons from the surface into the
surrounding space. The term "electron emission" is also used as a synonym of
"emission". There are different types of electron emission. For example, the
primary emission is an electron emission which is due directly to the rise of the
temperature of a surface, the irradiation of a surface or the application of an
electric field to a surface. The secondary emission is due to the bombardment
of a surface by electrons or ions. It is found that the electron emission
increases in the high temperature area.
It has also been shown that the electron tube, or valve, is a device where
conduction occurs through a vacuum or a gas.
There are several electrodes in a vacuum tube. The electrode is a
conducting element that performs one or more functions. In all tubes there is a
cathode, or emitter which is made of metal. There is also an anode or plate.
If the function of the cathode is to emit electrons, the function of the anode
or plate is to collect electrons. But in the diode there are only two electrodes.
The function of the diode may be described as following. The electrons are
emitted from the cathode when it is heated. The anode is given a positive
potential with respect to that of the cathode. In radio work, vacuum tubes may
be used as amplifiers.
In order to study electronics, it is also necessary to know such term as
frequency. The frequency is the number of cycles per second.
At the same time as electronics deals with the conduction of electricity
through gases, it must be mentioned that they are poor conductors.
Conductors offer little resistance to the flow of an electric current but
materials which offer great resistance to the flow of current are considered
insulators.
SEMICONDUCTORS
It is well known that transistors are used when efficient amplification is
required within a small space. The use of semiconductor devices is, therefore,
5
one of the means of the solution of two important problems such as
miniaturization and reliability. All types of electronic equipment with tubes, or
valves, can be made much better and more reliable with transistors or other
semiconductor devices, such as crystal diodes, etc. The transistor consists of
three electrodes. These are the base, the emitter and the collector. The base is
an electrode placed between the emitter and the collector. These electrodes
have different functions.
The total number of semiconductors produced in the world during each
year is now enormous although only few years have passed after their
development.
It has been already pointed out that a semiconductor is a material having
electrical properties intermediate between those of good electrical conductors
and those of insulators. It was found that the electrical properties of
semiconductors depend very much on their purity.
SOURCE OF VOLTAGE
Although a static charge can provide a great potential difference, the actual
flow of electrons is so short in time that very little electrical energy can be thus
obtained. For almost all electrical applications, a source of voltage that will
maintain current for a longer period of time (few hours or even days) is
required.
There are some methods of obtaining voltage. One of the methods of
obtaining voltage is by chemical means, such as in cells or batteries, which are
combinations of two or more cells. In case of this method, two dissimilar
materials, such as metals, are immersed into a solution, called the electrolyte.
The terminal connected to one metal will have an excess of electrons and the
terminal linked to the other - a deficiency of electrons. When connected to an
external wire, or conductor, electrons will flow steadily through the conductor
by the continuous action of the electrolyte on the dissimilar metals.
Another method of obtaining voltage is by magnetic means. Moving
electrons set up a magnetic field at right angles to the direction of current, and,
conversely, a moving magnetic field produces a current at right angles to the
magnetic field. If a conductor is moved through the lines of force between two
magnets, or the lines of force in the field of another conductor, a current will
be produced in it. This means is the most practical and widely used of all
sources of electricity.
ELECTRIC CIRCUITS
In general, an electric circuit is considered to be a path along which
electrons pass from the negative to the positive side of the voltage applied. It is
6
well known that the purpose of almost any electric circuit is to perform work
of some nature. For this purpose, effective control over the three parts of
which an electric circuit consists must be obtained. For a given voltage, current
can be controlled by a variation of the resistance offered to electron
movement. Therefore, resistance is specially introduced into electric circuits
for definite purposes, depending upon the particular type of circuit and the
purpose for which it is designed.
Although some resistance may be found in any conductor, the term
"resistor" will be used here only for a device whose specific purpose is to
reduce or control the amount of the current or vary the voltage within a circuit.
There are four types of arrangements of resistors in a circuit. A simple circuit
may consist of three parts: the source of power, the conductor to transmit the
current, and the transistor t to use the electrical energy. There is an arrangement
known as a series circuit. In addition to the essential parts of which a simple
circuit consists, there is another resistor in series with a special arrangement.
These two resistors may or may not be of the same value, depending upon the
purpose for which the circuit is designed. There may be an arrangement known
as a parallel circuit. In this arrangement the amount of voltage applied across the
two resistors will be equal to that of the battery voltage.
RESISTORS
Any resistor may be considered as a conductor across which high voltage
will produce only a small current. Resistors are widely used. They are
integrated into a circuit to produce certain conditions of operation. Resistors
used in a particular circuit are first chosen for their index of ohmic value, then
for their index of power handling capabilities. When there is a current in a
resistor, electrical energy is converted into heat. The amount of heat developed
is proportional to the current produced in the resistor and the voltage causing
the current. For example, a resistor can be used to limit current in one circuit,
decrease the voltage at a given point within another, or provide several values
of voltage from a common source in a third one.
CAPACITANCE
The establishment of an electric field in a capacitor is the result of a
property of a circuit known as the capacitance. A capacitor, or condenser, can
be considered as a device for storing electric charge. Capacitors may consist of
large plates with air as a dielectric or may be of compact form with thin
material coatings on either side of the dielectric. When an electric pressure is
applied across the plates of the capacitor, it becomes charged, and the quantity
7
of electricity which the capacitor can store is proportional to the charging
voltage and the size of the capacitor. This quantity is defined by the following
equation: Q = CV, where Q is determined in terms of electricity in coulombs,
С is determined in terms of capacitance in farads and V is voltage.
TRANSISTORS
The transistor is like a crystal diode, except that the emitter and the
collector separated by a few thousands of an inch touch the surface of the
crystal. Electrical contact to the bottom of the Germanium crystal is made
through the metallic base upon which it rests.
The basic transistor circuit is shown in Fig. l.
There are two circuits, one of which contains the emitter and the crystal
(base), the other containing the collector and the crystal. The battery "A" in the
emitter-base circuit makes the emitter positive with respect to the base. Thus
current flows in the forward direction and the resistance offered by the crystal
is low.
The battery "B" in the collector-base circuit makes the collector negative
with respect to the base. This is the reverse direction and the crystal offers a
very high resistance to the current flow. The flow of current in the emitter-base
circuits causes current to flow in the collector-base circuit. And the greater the
current flow in the emitter-base circuit, the greater the current flow in the
collector-base circuit will be.
VIII. Найдите в тексте ответы на вопросы:
1. What types of electric current do you know? 2. What current is the term DC
applied to? 3. How does the current in the AC circuit flow? 4. What is the
function of a resistor? 5. What is a conductor? 6. What does electronics deal
with?
8
IX. Прочтите и переведите следующие сочетания:
a) development of science, a fundamental problem, an electric circuit, an
electronic device, positive value, the transfer of electricity, electron emission,
potential difference;
b) a high energy particle; negative electrons flow; electrical energy converter;
an emitter-base circuit.
X. Запомните значения данных слов:
понятие,
idea - term - notion - concept - conception
представление
значение
meaning - sense - value - bearing - implication importance – significance
цель
aim - end - intent - goal - target - object
средство
aid - means - tool - device - instrument -apparatus technique - appliance
XI. Дайте русские эквиваленты:
a) to learn - to study - to investigate - to explore;
b) usual - common - ordinary - customary;
c) to analyse - to research - to inquire;
d) to prove – to establish - to argue - to demonstrate - to give evidence.
XII. Найдите в тексте подтверждение данной информации:
a) electronics is the field of science and engineering dealing with the
conduction of electricity in electron devices;
b) there are actually three types of current: conduction current, convection
current and displacement current;
c) a semiconductor is a material having electrical properties intermediate
between those of good electrical conductors and those of insulators.
XIII. Напишите сочинение на тему: "Properties of an Electric Circuit Direct and Alternating Currents."
XIV. Сделайте сообщения на следующие темы:
а) электрический ток;
б) проводники и диэлектрики;
в) основы электроники.
9
UNIT 2. LASERS
I.
II.
Прочтите и запомните эти слова:
aim
amplification
arrow
beam
bow
communication
drilling
liquid
message
property
ray
scattering
solid
substance
target
wave
weapon
welding
цель
усиление
стрела
луч
лук
связь
сверление
жидкость, жидкий
сообщение
свойство
луч
рассеивание
твердое тело
вещество
цель
волна
оружие
сварка
П. Определите по суффиксам, к каким частям речи относятся слова,
переведите их:
distance; communication; telegraph; complex; electromagnetic; equipment;
determination; conclusion; variable; development.
III. Переведите глаголы из первой колонки, взяв за основу значение
существительного с тем же корнем. Запомните их:
to depend
to support
to act
to invent
to produce
to differ
to inform
to locate
10
……………
……………
……………
……………
……………
……………
……………
……………
dependence
support
activity
invention
production
difference
information
location
зависимость
поддержка
деятельность
изобретение
производство
разница
сведения
местонахождение
to perform
……………
performance
исполнение
IV. Образуйте наречия от следующих прилагательных:
fundamental, individual, mechanical, proportional, wide, accurate, easy, normal.
V. Переведите исходные и производные слова, добавляя отрицательный
префикс:
un-: known, wanted, suitable, common, reasonable
in-: dependent, efficient, ability, correct, different, human
im-: possible, perfect, proper
ir-: rational, regular, relevant
non-: specialist, sense, essential
mis-: understanding, calculation, pronunciation
dis-: information, agreement, belief
il-: logical, legal, limitable.
VI. Образуйте прилагательные от следующих существительных с
помощью суффиксов -ful; -ant; -ent; -al. Переведите исходные и
производные формы:
usage, power, success, importance, difference, experiment, structure.
VII. Прочтите и переведите текст. Ответьте на следующие вопросы:
a) Is the text intended for students, specialists, or general readers?
b) Is the purpose of the text to teach a subject, to interest people in a new
subject, to provide new information, to tell people how to do something?
LASERS AND THEIR USES
Be it communications, medicine, industry, military operations or scientific
research, there is a new device for advancement, and that is the laser. It is a
device that amplifies (strengthens) light and as a result produces a thin intense
beam.
A beam of light is made to hit an object. This causes the object, which gets
stimulated by the light beam, to emit radiation. The radiation then strengthens
the original light beam and eventually turns it into a laser beam. The word
LASER stands for Light Amplification by Stimulated Emission of Radiation.
Is laser light the same as an ordinary beam of light? No, it’s not. An
ordinary beam of light is highly incoherent. It consists of a number of rays of
different wave lengths. These different wave lengths interfere with each other
and cancel each other out. An ordinary light beam is therefore quite weak; it
11
also spreads out widely and so gets scattered and lost. A laser beam on the
other hand, consists of light rays of a single wave length, which reinforce and
build each other up. The beam is therefore extremely powerful and can be
concentrated in a very narrow area.
The principle behind the working of the laser is the same as the one behind
the functioning of the bow-and-arrow. The comparison between the laser and
the bow-and-arrow is quite an apt one, since lasers were originally meant to be
developed as military weapons.
When an archer draws back the bow string, he transfers power from his arms
to the bow; the power getting stored in the tensioned bow in the form of potential
energy. The archer then takes aim and releases the string. The string "snaps
back" and the potential energy in it is converted instantaneously into kinetic
energy. It is this kinetic energy which drives the arrow forward, towards the
target.
In a similar fashion, lasers store energy in electrons or molecules of the
material being stimulated (these being the equivalent of the bow string),
concentrate it, and then release it in the form of powerful beams.
This process takes place because of the special properties that electrons (in
some cases) and molecules (in other cases) of substances that are capable of
being stimulated, possess. So when a beam of light is made to fall on the right
type of material, its electrons absorb the beam's energy.
Duly stimulated they expand, becoming bigger and bigger. However, there
is a limit to their expansion: when they are stimulated beyond that, they "snap
back" to their normal size, simultaneously releasing the stored energy in the
form of photons (basic particles of energy).
In the same way, molecules of other suitable materials when duly
stimulated, store the applied energy by absorbing it and thereby undergo a
change of geometry or shape. As the stimulation continues, their geometry
keeps on changing till a limit is reached. Further stimulation thereafter causes
the molecules to "snap back" and regain their original layout. In doing so, they
also release the stored energy in the form of photons.
The basic parts of a laser include a power source and a light-amplifying
substance. The power source provides the initial energy that causes the atoms
in the light-amplifying substance to get stimulated. The total energy produced
by a laser is always less than the energy produced by its power source. But the
laser produces a much more intense light in a concentrated form.
There are three major kinds of lasers, based on the type of their lightamplifying substance. Solid lasers use a crystal, glass, or a semiconductor as their
light-amplifying substance. A semiconductor conducts electricity, but not as well
12
as true conductors such as copper or iron. Gas lasers have a gas, or a mixture of
gases such as argon and helium-neon, as their light-amplifying substance.
Carbon dioxide gas lasers are the most widely used. Liquid lasers use a dye, such
as rhodamine 6G (краситель родамин), dissolved in menthol or a similar liquid.
A laser uses a substance which is capable of being stimulated. This is
placed in the middle of the device, and two mirrors are placed at either end.
One of the mirrors is only partly silvered. A beam of light is then made to
impinge on the substance. The substance gets stimulated and releases photons.
The photons bounce off the mirrors, hit the substance, and cause it to release
more photons. The ray of light so formed keeps on bouncing back and forth
between the mirrors and continuously stimulates more and more electrons (or
molecules) of the substance. This reinforces it continuously. Eventually the ray
becomes so powerful that it bursts out of the partially silvered end, and
emerges as an intense and concentrated beam.
Solid Lasers
Crystal lasers use a fluorescent crystal, such as a ruby. The power for a
ruby laser comes from a flash tube which is coiled around it. A brilliant flash
of light from this tube stimulates a large number of chromium ions in the ruby,
which in turn produce the laser beam. A ruby laser can normally produce light
only in bursts. Its beam can burn a hole through hard materials like steel, in a
single burst. Another type of crystal laser, called the NdYAG (neodymium
yttrium aluminium garnet, неодим-иттрий-алюминиевый гранат) laser,
produces a continuous beam of light and is used as a drill or as a range finder.
Glass lasers use glass as their light-amplifying substance and produce light
in bursts. They are used in experiments with plasmas.
Semiconductor lasers have a tiny cube of a semiconductor as their lightamplifying substance. A current passing through the semiconductor produces
coherent light. Their small size helps in carrying telephone, television and
digital data signals through a glass-fibre, via the coherent (laser) beam.
Gas lasers have several power sources, including chemical reactions,
electric current, electron beams and ultraviolet rays. Most gas lasers produce a
continuous beam of light and are used in communications, measuring, and
medicine.
Liquid lasers produce both bursts of light and continuous light. Bursts of
light are produced by liquid lasers that use a flash tube as their power source
and those that produce a continuous light use gas lasers for the initial power.
The liquid is contained in a glass tube. Liquid lasers are used to study the
properties of atomic and molecular systems.
13
The basic principles behind the stimulated emission process were explained
around 1917 by Albert Einstein, one of the greatest of all modern scientists.
The idea of the laser was conceived during the late 1950's and the device was
developed in the 1960's. Two physicists from the United States, Arthur L.
Schawlow and C. H. Townes, and the Russian physicists N. G. Basov and A.
M. Prokhorov proposed the idea of the laser. But it was Theodore H. Maiman
of the United States who built the first laser, a ruby laser, and operated it for
the first time in 1960. The following year, Ali Javan of the United States
operated the first gas laser. In 1966 Peter Sorokin operated the first liquid
laser.
Thereafter, the number of applications that lasers began being put to grew
at a steady pace, as more and more research was carried out. New uses for this
concentrated beam of light are being constantly found.
Communication
A laser beam can be used to carry voice communication between two
points, irrespective of the distance between them. A laser beam has a much
higher frequency than radio waves, and so can carry much more information
and can transmit several telephone calls and television programmes at the
same time. A laser produces a highly directional beam and so can transmit
information with little interference. Messages can be telegraphed, teleprinted
or faxed with the help of laser light. The narrow width of the laser beam
prevents the interception of secret messages unless an outsider is positioned in
the path of the beam. And in that case, the message will get cut off, thereby
alerting the sender and the receiver.
Electronics
Manufacture of chips and electronic components
Lasers are used for etching (cutting) the extremely fine circuits that are
required to be made on electronic chips, that are used in computers,
calculators, watches and other electronic products. Exact control of the laser
beam is possible and this makes such etching quite easy. In the same way,
other electronic components can be cut and shaped very accurately using laser
beams.
Cleaning of miniature circuits
Dirt, dust and other impurities often get into miniature circuits. Physical
cleaning, even if possible, can damage the circuits. Lasers can be used to clear
out (by controlled burning) all external matter, leaving the miniature circuit
completely clean, intact and unharmed.
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Entertainment
Nowadays laser beams are being used in lieu of needles to play records.
The beam, projected by the head which is positioned above the record, hits the
grooves in the record and bounces back. In doing so, it measures the
dimensions of the grooves; these depend on the type of music recorded, and
the information recorded by the beam can thus be used to reproduce the
original sound. The advantage of using a laser beam instead of a needle is that
there is no wear and tear on the record and so it stays like new, no matter how
many times it is played. Similarly, lasers can be used for playing compact
discs.
Medicine
The laser beam is used by eye specialists to correct a condition called
retinal detachment (отслоение сетчатки). The laser beam is aimed into the
patient's eye and is focussed on the retina. This helps to weld the loose retina
back into place.
It is also used for the removal of cataracts (катаракта) in the eye. This is an
easy and quick process as against normal surgery which can lead to
complications.
VII. Найдите в тексте ответы на вопросы:
1. What is the laser? 2. What are the features that make lasers useful for many
applications? 3. In what fields have lasers been applied? 4. What advantages
has the laser for welding? 5. How are lasers used in electronics? 6. What are
three major kinds of lasers?
VIII. Переведите следующие сочетания:
electron beam, electron beam welding, electron device, electron beam device,
high precision, high frequency, high frequency signal, light amplification,
voice communication, television programmes.
IX. Укажите, с какими заимствованными русским языком словами
ассоциируются английские слова:
experiment, structure, component, function, military, guide, assembly.
X. Дайте русские эквиваленты:
facts - data - information - intelligence;
sign - number - figure – character.
XI. Запомните значения данных слов. Переведите предложения на
15
русский язык:
mean - средний; среднее число
means - средство
to mean - значить, означать
meaning - значение
by means of - посредством
by no means – ни в коем случае
1. The year mean temperature in our city is about +8°C. 2. Electrical
typewriters and keyboard devices are the common means of input into a
computer. 3. This means that the ROM is the permanent memory chip for
program storage. 4. By means of arranging memory registers inside hardware
it is possible to store information and instructions. 5. By no means the
computer can substitute a human being in all respects.
XII. Найдите в тексте подтверждение данной информации:
a) a laser is a device that amplifies light and as a result produces a thin intense
beam;
b) the basic parts of a laser include a power source and a light-amplifying
substance;
c) there are three major kinds of lasers, based on the type of their lightamplifying substance.
XIII. Напишите сочинение на тему: "Применение лазера".
XIV. Сделайте сообщения на следующие темы:
а) основные принципы конструкции лазера;
б) какими бывают лазеры;
в) лазер как средство связи.
UNIT 3. COMPUTERS
I. Прочтите и запомните эти слова и словосочетания:
analogue computer
аналоговый компьютер
bit
бит, (двоичный) разряд
byte
байт; слот
card
перфокарта
chip
чип, кристалл
digit
цифра; число; разряд; символ; знак
digital computer
цифровой компьютер
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floppy disk
general-purpose computer
hardware
keyboard
memory
processing
punch
гибкий диск
универсальный компьютер
аппаратура, аппаратное обеспечение ЭВМ
клавиатура, коммутационная панель
память, запоминающее устройство
обработка
пробивка, перфорация
II. Назовите глаголы, от которых образованы следующие
существительные. Переведите исходные и производные слова:
addition; computation; information; performance; operation, subtraction;
multiplication; division; measurement.
III. Образуйте существительные от следующих глаголов с помощью
суффиксов:
-ment: to arrange, to require, to state, to develop, to measure;
-sion: to decide, to include, to conclude;
-ion: to subtract, to select, to act, to construct;
-ation: to inform, to combine, to determine, to represent, to integrate.
IV. Переведите, обращая внимание на значение префикса multi-:
multimode, multipurpose, multifunction, multichannel, multinational.
V. Переведите прилагательные, обращая внимание на значение
суффикса -less:
powerless, motionless, waterless, careless, helpless.
VI. Образуйте существительные и прилагательные с помощью
указанных суффиксов. Переведите исходные и производные слова:
a) operate v - …… -or n; operate v - ……-ion n - …… -al adj;
b) form v - …… -tion n; form n - ……-al adj - …… -ity n;
c) effect n,v - …… -ive adj - …… -ness n;
d) create v - …… -tion n - …… -ive adj.
VII. Прочтите и переведите текст. Ответьте на следующие
вопросы:
a) Is the text intended for students, specialists, or general readers?
b) Is the purpose of the text to teach a subject, to interest people in a new
subject, to provide new information, to tell people how to do something?
17
с) does the text assume that the reader has a scientific background, is
familiar with computers, has a special knowledge of computing technique?
WHAT IS A COMPUTER?
A computer is an electronic machine which performs calculations, solves
problems and stores information. Its hallmark is its blinding speed and almost
unfailing accuracy. Today, computers are used in almost all fields - be it
education, research, business, journalism or even art.
But even before the computer machine was invented, there already existed
another kind of computer in the world - the human brain. The human brain
computer is smarter than any kind of computer. The reason is it can think.
Machine computers cannot think. They only do what people tell them to do.
There are two basic types of computers - analogue and digital. The
analogue computer operates on data based on various physical quantities, such
as voltage. The digital computer, on the other hand, works with numbers,
words and digits. The computer which combines the functions of these two,
and utilises both analogue and digital data, is called a hybrid computer.
Today, most of the computers that you see around you in offices, schools
and libraries are digital.
More than two thousand years ago, the abacus (абак, арабские счеты) was
invented. It is a simple frame with rods which have beads. These beads denote
numbers. To solve mathematical problems with the abacus is not just
interesting, but is also very graphic.
In 1642, a French scientist, Blaise Pascal, invented a machine which used
wheels, instead of beads, for adding and subtracting. Counting with wheels is
used even today in electric metre boxes, and in mileage metres in automobiles.
Then, a German mathematician, Gottfried W. Leibniz, developed a more
advanced version of Pascal's machine which could divide, multiply and extract
square roots. This is the machine which we know as the calculator.
Towards the end of the 18th century, Joseph Jacquard, a Frenchman, used
punched cards to control the pattern (узор, рисунок) on a loom (ткацкий
станок). Though this was not a computer, it sowed the seeds for the
development of computer technology. It helped to count and keep records.
Later, computers received "input" from holes punched onto cards or paper
tape, and a little later from computer keyboards.
Basing on these machines, an English inventor, Charles Babbage
developed the first automatic digital computer in the 1830s, and called it the
"analytical engine". This computer was designed to do arithmetical operations,
as well as suggest the best option based on its computations. However, the
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"analytical engine" was never completed, because techniques for fabricating
metal parts had not yet been developed.
The next step in the evolution of the modern computer can be attributed to
an English mathematician and logician, George Boole. Boole's system of
binary logic operators (e. g. AND, OR and NOT) became the basis of
computer theory and procedures. Even today it is referred to as "Boolean
algebra".
Any major invention is the result of the combined efforts of several
geniuses, who pick up from where some other scientists or inventors left off.
In this chain of events, the next major contributor was Herman Hollerith, a
statistician from the United States. Somewhere in the latter part of the 19th
century, he introduced punched cards in data processing. Punched cards are
based on the principle that a pattern of holes in perforated cards can be read
electrically, by a machine designed for this purpose.
The first fully electronic digital computer was built by J. Presper Eckert and
John W. Mauchly of the University of Pennsylvania, in the 1940s. It was called
ENIAC (Electronic Numerical Integrator And Calculator) and it became
operational in 1946. It was the first digital computer. Since then, computers
started being applied in almost every area of operation which required precision,
speed, calculation and quick results. The first machine, built by Charles Babbage
was quite bulky and the ENIAC was also quite big. Efforts were directed
towards reducing the size of the machine, while still retaining its basic
operational ability.
The first major breakthrough came in the 1980s with the fabrication of the
IC (Integrated Circuit), a device which consisted of hundreds of transistors,
diodes and resistors on a tiny silicon chip, the size of a finger nail. This not
only permitted a smaller size, but also higher speed at a lower cost.
The next major development was the LSI (Large-Scale Integration) by
which thousands of transistors, and related devices, could be packed onto a
single integrated circuit.
In the same sequence, the next step was the use of the VLSI (Very Large
Scale Integration) which has increased the functions of computers, and also its
memory and storage capacity. Whereas the LSI circuits could contain
thousands of components on a silicon chip less than 0.2 inch square, the VLSI
circuits could hold hundreds of thousands of parts within the same amount of
space. These developments led to cost reduction, which is probably one of the
main reasons why we get to see computers in schools, offices and even homes.
Computer hardware refers to the physical equipment that makes up a
computer system.
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The keyboard of a computer is very much like a typewriter keyboard. It has
3 sets of keys: alphabet keys, numeric keys and function and cursor keys. The
keyboard is used to send information to other parts of the computer. The
instructions typed out on the keyboard are called programmes. What you type
is displayed on the computer screen which is like a TV screen.
When the programme is completely typed, by typing RUN it gets started,
and the results are shown on the screen. Lists of information, pictures, maps
and video games are typed in the same way.
A computer displays the programme or information on the screen. If you
want this information on paper, a machine called a printer prints it out for you.
There are different kinds of printers. The simple ones print only letters and
numbers and a few other symbols. The better ones can print almost anything even pictures in bright colours.
CPU (Central Processing Unit)
This unit, called the processor, controls the order in which the computer
deals with information. Computer software consists of programmes or
information fed into the computer. This processor also does all the counting,
makes all the logical decisions and helps the computer parts to work together.
A CPU is a small wafer of silicon, called a "chip" only l/8th of an inch
square, and 1/100th of an inch thick. Since the actual chip is so small, it is
embedded in a black plastic slab called a DIP (Dual Inline Package) that has
connectors built into its edges. The connectors, called pins, plug into the main
circuit board of the system unit, and carry data to and from the CPU.
A chip called the interpreter changes BASIC words into special numbers,
called binary numbers. Other chips may make sounds and pictures.
The processor has to perform two main types of functions: arithmetic and
control. For these tasks, the CPU has 2 functional parts - an ALU (Arithmetic
and Logic Unit) and a CU (Control Unit). The ALU contains the circuits and
special storage locations used to perform mathematical operations. The CU is
the control unit which keeps the processing in progress, moving from one
instruction to another as the programme requires. It also initiates and stops
input and output operations, and moves data between the storage and the ALU.
Memory
All computers have a memory. They remember facts and instructions.
There are computer chips which cannot do any computing function, but only
store information. They are called memory chips.
Memory is measured in bits and bytes. All information, fed into the
20
computer is changed into digits or numbers called binary numbers. The binary
system uses only two digits; 0 and 1. These digits are called bits. Different
combinations of bits represent letters, symbols, and decimal numerals. Each
such combination of bits is called a byte. There are two kinds of memory chips
in most of the PCs.
RAM (Random Access Memory)
This can also be read as Removable Any Minute memory. It is that area of
the main memory where information can be written in and read from. When a
program is read off a disk, it is written into RAM. But, RAM stores
information only while the computer is on. Once it is turned off, all data stored
in it is lost. For data consisted in RAM requiring storage, copies have to be
made either on another floppy or on the hard disk. Information in RAM can be
put on the tape very easily often by just typing SAVE on the keyboard. When
the information is needed again, it can be brought from the tape into the
computer's RAM, often by just typing LOAD.
The 3 main characteristics of RAM are: it provides both reading and
writing ability; it permits the recording of new information over previously
stored data, and, finally, its access time is independent of the sequence in
which bits of information were recorded. A PC can have between 64 Kb to
640 Kb of RAM in it. Memory size is expressed as a power of 2. Since 210 =
1024, so 1 Kb = 1024 bytes. A computer with 64 Kb of RAM is said to have
storage space for 64,000 bytes of information, but actually that RAM would
hold 65,536 bytes (64 x 1024). Extra RAM can be added to the PC by either
plugging in another bank of chips into the main circuit board or by adding an
extra circuit board with RAM chips in one of the PC's five expansion slots.
ROM (Read Only Memory)
This area of memory can only be read from and not written into. The 2
main characteristics of ROM memory are: it keeps its data even after the
power is turned off, and new data cannot be entered into ROM.
ROM chips have programmes already loaded into them before they are put
into the PC. These are programmes which the machine uses frequently and
needs to have on hand. ROM is typically used for software which translates
programme languages into the code of the machine. ROM is ideal for
programmes which have to be used repeatedly without any modification.
Nowadays, floppies are mostly used for data storage. Like an audio or
video cassette, a floppy is used to record data, and, likewise, existing data can
also be erased by recording new data onto it.
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There are three main types of ROM. When a manufacturer preprogrammes
a ROM at the time when a device is being manufactured, it is called a masked
ROM. This type of ROM cannot be changed by the user. A Programmable
ROM (PROM) is supplied without an inbuilt programme. However, once a
PROM has been programmed, it cannot be changed. The Erasable PROM
(EPROM) is a modification of the PROM, and offers the facility of
reprogramming.
Depending on the size of the memory and the processing speed, there are 4
sizes of computers: 1) a Micro Computer, which is small, and is the most
common computer, usually it is single-user driven; 2) a Mini Computer, which
can support 12-30 users at once; 3) a Mainframe Computer, which services
several hundreds of users and is used by large organizations; 4) a Super
Computer, which is used for highly complex scientific tasks.
Disk Drives
Using tapes is slow. A faster way of saving information is by the use of a
machine called a disk drive. A disk drive is a machine that, among other
things, reads 0's and 1's magnetically encoded onto disks. This information
then goes to the memory. A disk system provides quick and direct access to
specific information located anywhere on a disk. Flexible magnetic disks,
called floppy disks, are widely used to provide input to personal computers.
Floppy Disks
Floppy disks are used today not only for the transport and exchange of
data, but also for storing data. It is made of mylar or polyurethane coated with
metal oxide. The inside of the jacket is lined with a feltlike material that cleans
and sometimes lubricates the disk as it turns. The Index hole on the floppy
helps the PC to count disk rotations. The Write-Protect notch is covered with a
tape, if data stored in a floppy is only to be read, and not altered. The Access
hole allows the drive to read and write data. The alignment notches fit the disk
snugly into the drive. When the disk drive is working, the red drive light
glows. This indicates that the recording head is reading or writing on the disk.
Hard Disks
Usually hard disks of 10 Mb are used. This means that they can hold 10
Mb of data, which is equivalent to 3000 pages of single spaced type-written
text. Hard disks range from 5 Mb to 70 Mb. Whereas a floppy is organised
into 40 tracks and 8 or 9 sectors, the hard disk is organised into 306 tracks and
17 sectors.
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Modems
Modems are devices that allow computers to communicate with other
computers by using telephone lines. A modem translates sounds into tones that
represent binary numbers. It can send the tones over the phone lines to other
modems.
Other input devices are a joystick and a mouse for moving figures about on
a screen and a graphic tablet consisting of a pad and a special pen for
producing illustrations. Voice activators enable computers to understand
spoken words.
Expansion Slots
These are empty connectors inside the PC for adding components. An IBM
PC has 5 slots to add extra circuits. Two of these are filled with the diskcontroller card (which controls the operations of the disk) and the videodisplay card (which controls the display screen or monitor). This leaves the
user to install 3 other add-ons to his PC. This might include common boards or
cards to control the printer or a modem to add extra RAM.
Interfaces
Also called a port or a connector, these are sockets outside the system unit
for adding components. There are two types of port: a parallel port, in which
several information signals are loaded and sent at once, and a serial port, in
which each electronic signal is loaded and sent one at a time.
For example, the connection most often used to connect the printer (parallel
port) is similar to the usual modem connection (serial port).
Every time a computer is turned on, it does a self-diagnostic check. One
by one it makes sure all its memory chips are functioning properly before it
starts its work. This is referred to as booting a system or a start-up of a
computer.
Computer Language
A computer, as you know, is an electronic device and its brain consists
of numerous switches which can be switched on or off. This means that the
computer understands the language of two words -"on" and "off". In
numeric terms, off = 0 and on = 1. This system is called the binary system.
The first computers could be operated only by setting a long series of
switches on or off. But we do not speak in binary terms. So, computer
languages were created to make computers easy to use.
A computer language is an interpreter which uses terms which both the
23
user and the computer understand. The most commonly used languages are
BASIC, COBOL, FORTRAN, C and ADA.
Software
Software is a recording of a list of commands that someone has written
in a computer language. Software is written to suit one's own specifications
and requirements.
Now, the next time you work on the computer, you will probably
understand this wonder machine and its inner mechanisms, as well as its
usefulness - be it for a game of chess or for shooting missiles.
VIII. Найдите в тексте ответы на вопросы:
1. What is a computer? 2. What kinds of operations does an automatic
digital computer perform? 3. What is a very simple example of a computer?
4. Why does a computer take in information and store it? 5. When was the
first fully electronic digital computer built? 6. How does an analog
computer compute? 7. What are the main functions of the processor? 8.
How does a digital computer compute? 9. What is hardware? 10. What is
software? 11. What is the difference between RAM and ROM?
IX. Прочтите и переведите следующие сочетания:
a memory location, numerical measurements, a punched card, a punched
tape, data-handling equipment, auxiliary devices, a storage device, Large
Scale Integration.
X. Запомните значения данных слов. Переведите предложения на
русский язык:
to set - ставить, помещать, устанавливать
to set aside - откладывать
to set up - основывать, учреждать
a set – набор, комплект, множество, прибор
a set of - ряд
to preset - заранее помещать
1. The first Russian Academy of Sciences was set up by Peter I in 1724. 2. The
set of logical operations include moving, comparing, translating, bit
connecting, editing. 3. Several bits of an instruction are set aside to determine
the operation code. 4. The address of an instruction must be preset before
making a block diagram.
24
XI. Дайте русские эквиваленты:
ALU, CAD, CAM, CPU, IBM, MOS, RAM, ROM, LSI
XII. Найдите в тексте подтверждение данной информации:
a) in 1642 a French scientist, Blaise Pascal, invented a machine which used
wheels, instead of beads, for adding and subtracting;
b) any major invention is the result of the combined efforts of several geniuses,
who pick up from where some other scientists or inventors left off;
c) a computer is an electronic device and its brain consists of numerous
switches which can be switched on or off. This means that the computer
understands the language of two words - "on" and "off".
XIII. Напишите сочинение на тему: "From the History of the Computer."
XIV. Сделайте сообщения на следующие темы:
а) появление ЭВМ - результат настойчивого поиска средств
автоматизации вычислений;
б) революционные изменения в архитектуре и программном обеспечении
ЭВМ;
в) компьютеры пятого поколения.
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UNIT 4. ROBOTS
I. Прочтите и запомните эти слова и словосочетания:
шарнирная рука
arm
axis
(в робототехнике) степень подвижности; ось
control system
система управления
controller
устройство управления
degree of freedom
степень свободы
feedback
обратная связь
handling
манипулирование
joint
сочленение, шарнир (кинематическая пара)
gripper
захватное устройство, схват
part
деталь
power supply
подвод энергии, энергопитание
programmable machine программируемое устройство
remote control
дистанционное управление
sensory system
сенсорная система
wrist
(в робототехнике) устройство ориентации,
запястье
II. Назовите глаголы, от которых образованы следующие
существительные. Переведите исходные и производные слова:
production, movement, instruction, development, exploration.
Ш. Назовите прилагательные, от которых образованы следующие
наречия. Переведите исходные и производные слова:
generally, commonly, properly, finally, automatically, specially, usually.
IV. Назовите прилагательные, от которых образованы следующие
существительные. Переведите исходные и производные слова:
humanity, popularity, capability, intelligence.
V. Переведите исходные и производные слова. Где возможно, дайте
несколько вариантов:
a) apply - applicable – application; perceive - perceptive – perception; use useful – usefulness;
b) accurate - accuracy – inaccuracy; able - ability – disability; integral integration – disintegration;
c) assume - assumed – assumption; provide - provided – provision; develop 26
developed – development; instruct - instructed – instruction; move - moved –
movement;
d) detect - detected - detecting – detection; repeat - repeated - repetitive –
repetition; decide - decided - decisive – decision.
VI. Переведите, обращая внимание на значение префиксов pre- и re-:
predetermined, preset, retranslate, reconstruct, reproduce, prearrange, rearrange,
preheating, reestablish.
VII. Прочтите и переведите текст. Ответьте на следующие вопросы:
a) Is the text intended for students, specialists, or general readers?
b) Is the purpose of the text to teach a subject, to interest people in a new subject,
to provide new information, to tell people how to do something?
c) does the text assume that the reader has a scientific background, is familiar
with robotics, has a special knowledge of robots?
THE DEVELOPMENT OF TRUE ROBOTS
For centuries people have dreamed of having a perfect slave - a robot worker
to do their work for them. The name "robot" was first used in 1920, in a play
called Rossum's Universal Robots by Karel Čapek, a Czechoslovakian science
fiction author. The term "robot" is derived from the Czech word "robota",
meaning "forced labour".
The origin of robots goes as far back in history as the prehistoric man
himself. The Stone Age man made the first simple stone tools. With the passage
of time, the wheel, the lever and the pulley were invented. These aids multiplied
the power of the human muscle, though man still had to control them.
The next step was the development of powered machines, which derived
their energy from chemical, mechanical and, finally, nuclear sources. In 1801, J.
M. Jacquard, a French inventor, devised an automatic loom (ткацкий станок)
which produced complex patterns (сложный узор, рисунок) by controlling the
motions of many shuttles (челнок, уток) of differently coloured threads. In the
latter part of the 19th century Charles Babbage invented a complex, mechanical
"analytical engine" which could also make decisions along with routine
calculations. The age of automation had started.
A mechanical copy of a living being is called an automaton. Automata were
made for fun. In the late 18th century, a Swiss clockmaker made a model of a
child writing at a desk. The child dipped his pen in an inkpot, shook off the
excess ink and then wrote in the best handwriting. In the same century, a
27
German, Baron Wolfgang von Kempelen made a mechanical, life-size, chess
player (with a still rife speculation whether it might not have been a piece of
trickery). Automata are still popular. Some of the best ones can be found in
"Disneyland" in the USA.
In the 20th century, science fiction and feature films popularised the concept
of "iron men" or robots. Movies like Target Earth (1954), Phantom Empire
(1935), Lombies of the Stratosphere (1952) and the most popular Star Wars
(1977) presented the robots as having "brains", and there being "good" robots
and "bad" robots. But these were not robots in the real sense of the term. They
were "androids". Off the screen, engineers were trying to design android-like
robots, but were finding it increasingly difficult.
A robot is an automatically operated machine. It is a computer "brain" which
can be taught or programmed to perform human tasks automatically. The
development of true robots was made possible only by the invention of the
silicon chip in computers, which provides robots with brains.
Robots, generally speaking, are mechanical arms controlled by computers to
accomplish those handling activities of men which are repetitive or hazardous by
nature. Robot workers never get tired or bored, or make a careless mistake. Areas
where robots are highly useful are dangerous areas, e.g. a bomb-detecting robot
(робот-сапер) can help to protect a man from danger. They can be used in
environments which are harsh or dangerous such as radiation zones, space, coalmines and under-sea areas.
Robots that work under water are unmanned, submarine vehicles, linked by
cable or sonar links to human operators. They perform tasks such as inspection
of pipelines or location of shipwrecks. They are also used for undersea drilling
and mining practices.
In space, robots are used for space exploration and they are equipped with
automated problem-solving and decision-making capabilities by the onboard
computer system. The first robots in space were in the Surveyor series of
unmanned Lunar Landers sent out by the United States. But the Soviets were
the first to demonstrate remote control. Their spacecrafts carried stereo cameras
to provide human operators with a view of the surface while driving around the
moon. The first advanced robots in space were the two Viking Landers sent by
the United States which landed on the Mars in 1976.
Another application, which caught the attention of the masses in the United
States, was the robot as a bartender. A lightweight microphone allows the waiter
to communicate with the robot-controlled bar, and to place orders. The order can
be placed directly from the customer's table. The drinks are poured and mixed
automatically, and are then served by the waiters. Meanwhile, the computer does
28
stocktaking (рассчитывает счет) and cash control, thereby leaving very little
chance of inaccuracy.
Robots have found their way into other areas too. All kinds of small mobile
robots are available for use at home. Small robot arms, small enough to sit on a
desk, can be now bought. They are usually driven by electric motors, but may
also be pneumatic (air driven) or hydraulic (water driven), and can lift weights of
about one kilogram or more. All that is needed to run a small robot at home is a
micro computer.
Robots are especially useful in industry to produce a wide range of goods
with precision. In the automobile industry, robots are used to lift, weld and spray
paint.
The movements of the "mechanical arms" are recorded in the computer's
memory, so that they can be repeated precisely. There are some robots which
even have a sensor device to help them correct their own movements, if they are
not going according to the programmed instructions.
Robots can help disabled people feed themselves, or use a type-writer and
can act as guides to the blind. In dentistry schools, a robot is used to teach
students. It gives a loud electronic "ouch" if they drill too far into its tooth.
In Australia, sheep-shearing robots can fleece a sheep in fifteen seconds,
without even a nick. But children will not be too happy with "Big Mac", a robot
that phones and tells their parents if they do not do their homework.
Movies and fiction have made robots popular as brainy iron-men with
intelligence enough to even overtake men. Based on this, the engineers are
working on the design of a micro-robot and a whole range of robotic games for
children. Another interesting development in the field of robotics is sport. Here
the combat is between a man and a robot.
But how do all these robots work?
If you want to teach a robot how to open a window, there are four ways.
Show it by holding its "hand" and moving it through all the steps - reaching
out, taking hold of the handles, turning the handles, and finally, opening the
window. The robot records every movement and then, at a signal, plays back the
movements like a tape-recorder. This is especially useful for teaching skills like
paint spraying and welding.
Another way to teach a robot is by using a remote control device called a
"teaching pendant". This is a box attached to the robot's computer. It has
switches that operate the motors in each of its joints. The robot is taught to move
its arm to each position the job requires and then a "record" button is pressed so
that it will remember the position.
A more complicated way of teaching a robot is by writing a computer
29
programme, in a special language, to tell it how to move each of its parts. A
language called Logo is often used to teach people about robots. It is especially
designed to control simple mobile robots such as the turtle. It contains
instructions such as FORWARD 10 RIGHT 90 (which means "go forward 10
units and then turn 90 degrees to the right"). For industrial robots there are more
complicated languages.
Robots can learn by working a problem out for themselves. But very few
robots have been built that can do this. In the 1960s a robot called Shakey was
built at Stanford University. It could find its way round a room avoiding
obstacles which it could "see" with a TV camera. It could even find an electric
socket and recharge itself.
The industrial robots are generally made of three basic units: power supply,
the manipulator arm with joints and gripper, and the computerised control
system.
Power Supply
It is the power supply that produces a set of forces which move the parts of
the robot at its different joints. Three types of power supply are commonly used:
electric, hydraulic and pneumatic. Electric systems use AC (Alternating Current)
or DC (Direct Current) motors, with each joint of the robot being controlled by
an individual motor. Hydraulic systems use force provided by liquids, such as
oil, which is forced along the tubes, under high pressure. Pneumatic systems are
powered by compressed air, which makes it difficult to control complicated
procedures accurately.
The Arm
The visible part of the robot is the manipulator arm, with its gripper or
"end-effector" and joints. The joints are like those of human beings and are
capable of five basic types of movements: 1) Rectangular Coordinate, i.e.
movements along 3 basic axes, x, y, and z, or left-right, backward-forward and
up-down; 2) Cylindrical Coordinate, the type that can rotate around the
vertical axis; 3) Spherical Coordinate, the type achieving its vertical motion by
pivoting at the shoulder joint; 4) Revolute Coordinate, the type with joints at
the "shoulder", "elbow" and "wrist", closely resembling the human arm; and,
5) SCARA Systems, where SCARA stands for Selective Compliance Assembly
Robot Arm, in this all the joints being in the horizontal plane.
To define a robot, you also need to describe the number of degrees of
freedom it possesses. This is the number of axes on which the robot "arm" can
move. The human arm can move about on more than 20 axes. Even with six
degrees of freedom, the industrial robot has a long way to go before it can
equal the human arm.
The "end-effector" takes the place of the hand in the robot "arm". End30
effectors are for specific operations. Some commonly used ones are grippers,
suction pads, shovels and hooks. Robots in a factory can change their "endeffectors" to suit the particular job they are doing.
Control System
This is the third component of the robot. It not only directs the motion but is
also responsible for the sensory processing of the robot mechanisms. The
computer is used as the control system that contains sets of instructions which
direct the motor in the robot to bring about a certain specific motion or function.
For the control system to function properly, the robot sensory system gathers
specific information needed for adequate control of the robot. In the more
advanced systems, the sensory system of the robot maintains an internal model
of the environment to enable prediction and decision making. But it is not
enough for robots simply to perceive and understand the world around them; it is
just as important for them to be able to understand how their actions influence or
change the particular task at hand. This means that a robot has to have
"feedback".
In this age of information technology, robots have an important role to play.
The future might offer developments in the shape of completely automated and
unmanned factories or as domestic help in homes, or intelligent robots using their
skill and judgement in industry and space exploration. The turn of the century
could see some interesting developments in this field.
Will people control robots, making their own lives easier, or will robots be
uncontrolled? The use of robots by man could lead to greater unemployment.
But on the other hand, people will be free from boring, manual jobs and will
have the time to do jobs that satisfy their minds. So finally it is up to man.
However fast and accurate a robot be, it is man who directs and commands the
robot. It is man's brain which masters all things on Earth.
But using these powerful machines, perhaps we should follow the science
fiction writer, Isaac Asimov's rules about robots.
* A robot may not injure a human being or allow one to come to harm.
* A robot must obey orders given to it by human beings except when such
orders would break the first rule.
* A robot must protect itself as long as this does not make it break one of the
other rules.
VII. Найдите в тексте ответы на вопросы:
1. When was the name "robot" first used? 2. Can you render the history of robots
design? 3. What invention made possible the development of true robots? 4.
How do all robots work? 5. What are the three basic units of industrial robots? 6.
31
What is the meaning of the control system in the robot mechanism? 7. Where
can the robots be used?
VIII. Запомните значения данных слов и переведите предложения:
intelligence n - I) ум, интеллект, умственные способности; 2) сведение,
известие, информация, сообщение; 3) разведывательные данные, разведка;
4) сношения, связи
intelligent adj - умный, разумный, понятливый, смышленый,
понимающий, информированный, осведомленный
intelligently adv - умно, разумно, с пониманием дела
intellect n - интеллект
intellectual adj - умственный, интеллектуальный, мыслительный,
мыслящий, разумный, интеллигентный
intellectual(s) n - интеллигент; мыслящий человек; интеллигенция
intellectually adv - интеллектуально, умом, рассудком
reason n – разум, интеллект; здравый смысл, благоразумие
mind n – рассудок, разум; мнение
brain(s) n – головной мозг; рассудок, умственные способности
wit(s) n – ум, разум, соображение; остроумие
1. The human brain is so complex that the exact prediction of its behaviour is
impossible. 2. Artificial intelligence is the field of computer science. 3. Can
robots be made as intelligent as human beings? 4. The problem of testing a
machine to see whether it is intelligent was first discussed by the great British
logician and computer pioneer, Alan Turing. 5. Man knows his mind
insufficiently. 6. A man supplied with computers and robots -the products of
man's reason - thinks deeper and wider.
IX. Дайте русские эквиваленты:
1) bulky - large - enormous - prodigious;
2) subsequent - later - following;
3) vast - great - huge - extensive;
4) at the same time - simultaneously - concurrently;
5) essentially - substantially – largely.
X. Найдите в тексте подтверждение данной информации:
a) the robot records every movement and at a signal plays back the movements
like a tape-recorder;
b) all that is needed to run a small robot at home is a microcomputer;
32
c) the industrial robots are generally made of three basic units: power supply, the
manipulator arm with joints and a gripper and the computerised control system.
XI. Напишите сочинение на тему: "Robotics - fruitful field of Artificial
Intelligence".
XII. Сделайте сообщения на следующие темы:
а) история робототехники;
б) основные принципы конструкции роботов;
в) сферы применения роботов.
CONTENTS
UNIT 1.SOME FUNDAMENTALS OF ELECTRONICS…………. 1
UNIT 2. LASERS ………………………………………………….10
UNIT 3. COMPUTERS ……………………………………………17
UNIT 4. ROBOTS …………………………………………………26
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