Grammar: 1.Nominative Absolute Participle Clause
TEXT 12 A
The Fundamental Problems of Television.
The word “television” by common acceptance has come to mean the essentially instantaneous transmission, either by wire or radio, of moving pictures or images.
Essentially three steps are involved in television, namely: 1) the analysis of the light image into electrical signal; 2) the transmission of the electrical signal to the points of reception; and 3) the synthesis of a visible reproduction of the original image from the electrical signal.
The ordinary concept of a picture or image is that of a surface over which there is more or less continuous distribution of varying light and dark, the distribution changing smoothly with time to conform with motion in the picture. Here the brightness is a function of the three independent variables, X, Y and T, where X and Y are the horizontal and vertical position of any point on the picture and T is the time. Obviously, such a distribution cannot be transmitted over a single electrical communication channel where the current or voltage transmitted is the function of time only.
In order to overcome this fundamental difficulty it is necessary to take advantage of certain physiological limitations of sight to reduce the amount of information being transmitted. These limitations are the finite resolving power of the eye and the persistence of vision. If a picture is subdivided into a large number of small elements, with each element being uniformly shaded, the picture will still appear continuous, provided the elements are so small that they are not resolved by the eye. Thus a picture composed of a finite number of discrete elements is entirely satisfactory for viewing.
The illusion of continuous motion can be obtained as is done in the case of the cinema, if we form a series of static pictures in rapid succession, with one picture differing slightly from the preceding to correspond to the motion which has taken place in the scene (opera, play or sporting event) during the interval between pictures. From this it will be evident that the information known to be necessary to reconstruct a completely satisfactory visual representation of a moving picture, can be conveyed by transmission of the brightness values of a finite number of picture elements at finite rate. Therefore, the conditions found to be necessary for the transmission of moving pictures over an electrical communication channel are satisfied.
The picture to be transmitted is analyzed by the process known as scanning.
The scanning element at the transmitter end the exploring element moves in a continuous or discontinuous line covering the entire surface of the picture. In general the size of the exploring element is equal to a picture element or smaller then a picture element. It generates, either directly or indirectly, an electrical signal, which corresponds to the brightness of the area of the image on which it is located. As the exploring element moves along the scanning pattern over the surface of the picture the electrical signal varies forming a characteristic complex wave known as the video signal.
At the receiving end of the link there is another element the reproducing element which moves over the screen in a scanning pattern, which is geometrically similar to that at the transmitter. To obtain a picture at the receiver the scanning beam at the receiver must keep accurately in step with that at the transmitter: in other words, at any instant, both scanning beams must be moving over the same line of the image and must be at the same point in that time. Therefore, a reproduction of the picture being transmitted is formed on the screen of the receiver.
The scanning pattern at the transmitter, the exploring and reproducing elements and the communication channel connecting them are symbolically illustrated in the figure below.
Answer the questions:
- What does the word “television” mean?
- What are the main steps involved in television?
- What is the ordinary concept of a picture?
- What can be done in order to overcome the fundamental difficulty of transmitting information?
- How can the illusion of continuous motion be obtained?
- What is scanning? When and how is this process used?
- Where is a reproduction of the picture being transmitted formed?
- Translate the following words paying attention to the prefixes:
Subdivide, subdivision, subcommittee, subgroup, supernatural, supersonic, subsection, subtropical, subarctic, subsonic, superhuman, superheat, ultra-violet, ultramodern, ultra-short.
- Translate the sentences paying attention to the adverbs:
- It has been repeatedly pointed out that wave motion is associated with vibration of particles.
- Solid-propellant rockets have been gradually increasing their specific impulse.
- The navigation system will continuously determine position of the satellite around the Earth.
- When gases are highly compressed they are characterized by extreme lightness.
- A gas is composed of individual particles, which are constantly colliding with each other.
- Engineering mechanics is essentially a study of the effects of forces acting on bodies.
- Translate the sentences paying attention to the adverbs:
Extremely difficult problem
- Because there is no working fluid or energy source carried on the vehicle, the photon rocket is highly economical in weight.
- To utilize solar radiation very large surface areas are needed and they will be prohibitively heavy.
- Space travel is going to play an increasingly important part in our lives.
- The general activity of navigation in space without external assistance is still largely theoretical.
- At extremely high altitudes the different gases composing the atmosphere separate according to their densities.
- The air in the “standard” atmosphere was assumed to be perfectly dry.
- Translate the sentences paying attention to the participles:
- Operation of an ion rocket involves three principal processes: generation of ions, their acceleration by electrostatic field, and electrical neutralization of the resulting ion beam.
- A much less important though related problem is the study of interplanetary dust.
- The shape of the curve is similar to the curves of many associated phenomena.
- This figure illustrated diagrammatically the nature of the ground-based observations of the solar and related terrestrial disturbance phenomena.
- Translate the sentences paying attention to verb “involve” and the participle “involved”:
- Space flight involves many different problems varying greatly with different missions.
- Nuclear raditional involves the release of a considerable amount of energy.
- Teaching pilots to fly involves a great deal of training.
- Energy is involved in every motion, in every event.
- Liquid oxygen has been used in the industry for many years, and no great problems are involved.
- The technical problems involved in the construction of an ion rocket are considered in some detail below.
- Some of the forces involved in flight are lift, drag, thrust and gravity.
- It is the purpose of this chapter to discuss the general principles involved in the operation of electronic devices.
- We have to consider all the factors involved in the construction of rocket engines.
- The mathematical difficulties involved in an exact solution of the motion of two or more electrons revolving round a nucleus are very great indeed.
- Rocket propulsion differs from other propulsion methods only in the relative masses and velocities involved.
- The process involved aims at production of heavy water.
- The reduction of radiation intensities to a safe level for the personnel involved is not particularly difficult.
- When selecting the propellants to be used for any particular rocket there are obviously a great many considerations involved.
- Translate the sentences paying attention to the words “point” and “view”:
Point n, v
- Rotary motion of a body is such that every point of the body revolves in a circular path about some point, which serves as the axis of rotation.
- Thanks to radio aids airplanes can fly to the point of destination without a human pilot aboard.
- An important point to remember is that the missile itself is usually only a component of a complete weapon system.
- It is an interesting point that all devices and machines function usefully only when some sort of energy change takes place.
- To illustrate the point previously made about the importance of density, Table ІV shows the ranges of the gyro-controlled missile.
- From a physical standpoint, a gas is composed of individual particles, each in continual, irregular motion.
- It should be noted that up to this point the effects of side wind have not been taken into consideration.
- The magnetic compass points to the exact magnetic north at only a few places on the earth.
- It is well to point out here, that the source of the scattered energy is called “target”.
- The pilot must always have a good view from the cockpit.
- Aircraft piston engines may be classified from the point of view of the arrangement of their cylinders.
- The book provides an analysis of the action of semiconductors from the physics viewpoint.
- In view of the tremendous speed of light, its determination must require the measurements either of very long distances or of very short intervals.
- In view of the definite composition of compounds, we see an immediate distinction between compounds and mixtures.
- Immediately after Becquerels discovery of uranium rays the Curies made a careful study of all the then known elements by the electrical methods, with a view of determining whether or not the property of radioactivity was possessed by other substances.
- Air-to-surface missiles may be viewed as long-range aerial bombs possessing high accuracy.
- Translate the sentences paying attention to the words in bold type:
- The fundamentals of alternating current are presented in this chapter.
- Many variables involved in the selection of suitable fuels for gas-turbine engines.
- In all steam engines and turbines there are three basic essentials: 1) the source of heat; 2) the working agent; 3) the sink.
- Translate the sentences paying attention to the verb “provide” and the noun “provision”:
- The rocket engine provides the propulsive forces to accelerate the vehicle.
- We shall discuss now the evidence provided by cosmic observations.
- The rocket provides the only practical means needed to place an artificial satellite in an orbit about the Earth.
- Radioactive isotopes provide a new tool for industry and an instrument for scientific research.
- The International Geophysical Year provided the first occasion for a prolonged programme of cosmic ray observations throughout the world.
- The provision for power supply is a problem to be solved.
- In manned space systems, provision is made for maintenance and repair of the power system equipment during a mission.
- When placing the heat source in the vehicle, provision must be made for the heat shunting.
- Translate the sentences paying attention to the meaning of the words “provided”, “ provided that”, “ providing”:
- The density of a body can be found, providing its mass and volume are known.
- A satellite in orbit is acted upon by only one force, gravity, provided it is high enough to be free of air drag.
- With the rocket almost any chemicals can be used, provided that they react together and produce hot gases as end products.
- Provided the satellites kinetic energy is high enough to overpower gravity and drag, an object can orbit at any altitude around the Earth.
- Translate sentences paying attention to the function of the words “ provided ” and “ providing ”:
- If a short half-life-radioisotope is utilized in the heat source, excess fuel must be provided at the beginning of the mission.
- Newton not only demonstrated the nature of white light but also provided an explanation for the production of colored spectrum by a prism.
- Hookes law of elasticity, named after his discoverer, Robert Hooke (1635-1703), states that the deformation of a solid body is proportional to the force acting on it, provided the force does not exceed a certain limit.
- Experimental studies of plasma properties, although providing quantitative data at specific operating points, have not by now provided the desired relationship between these properties and thruster operating parameters.
- The velocity with which a gas will flow from one container to another may be obtained in the same manner as for a liquid, providing the density remains constant.
- Liquid oxygen systems are not at all dangerous in service, provided all the necessary safety measures are taken.
- It is possible for an object to revolve in a circular orbit about an attractive center, provided that the attractive force is of the right magnitude to give it the acceleration, which corresponds to the curvature, of the orbit.
- Translate sentences paying attention to the meanings of the noun “succession”:
- If we send sunlight through a prism, we get the well-known spectrum, in which all colors from red to violet are contained in a continuous succession.
- In an ordinary a. c. circuit the current goes through all its phases in succession.
- Pulse radar uses a succession of short pulses of radio-frequency energy.
- Translate the sentences paying attention to the meaning of the verb “locate”:
- All guided missiles need a system which will identify and locate the target.
- Radioisotopes are used as an inspection tool for locating damaged parts.
- The tanks may be located in the wings of the airplane.
Text 12 B
The Social History of Television as a Technology
- Study the text. Try to understand all details. Use a dictionary if necessary:
- It is often said that television has altered our world. The invention of television was no single event or series of events. It depended on a complex of inventions and developments in electricity, telegraphy, photography and motion pictures, and radio. It separated out as a specific technological objective in the period 1875-1890, and then, after a lag, developed as a specific technological enterprise from 1920 through to the first public television systems of the 1930s. Yet in each of these stages it depended on inventions made with other ends in view.
- Television, as an idea, was involved with many of these inventions. It is difficult to separate it, in its earliest stages, from phototelegraphy. The means of transmitting still pictures and moving pictures were actively sought and to a considerable extent discovered. The list is long even when selective: Careys electric eye in 1875, Nipkows scanning system in 1884; Brauns cathode-ray tube in 1897; Rosings cathode-ray receiver in 1907.
- Through this whole period two facts are evident: that a system of television was foreseen, and its means were being actively sought, but also that, by comparison with electrical generation and electrical telegraphy and telephony, where was very little social investment to bring the scattered work together. In 1923 Zworykin introduced the electronic television camera tube. Through the early 1920s Baird and Lenkins, separately and competitively, were working on systems using mechanical scanning. There was great rivalry between systems and there is still great controversy about contributions and priorities.
- What is interesting throughout is that in a number of complex and related fields, these systems of mobility and transfer in production and communication were at once incentives and responses within a phase of general social transformation. The decisive transformation of industrial production and its new social forms created new needs but also new possibilities, and the communication systems, down to television, were their outcome.
Motion pictures кіно
With other ends in view з іншими цілями
The list is long even when selective список довгий, навіть якщо він зроблений вибірково
To bring the scattered work together зєднати розрізнені роботи
There is still controversy about contribution and priorities все ще іде дискусія стосовно міри та пріоритету.
- Say whether the following statements are true or false:
- The invention of television was no single event or series of events. 2. In each of the stages the development of television depended on inventions made with other ends in view. 3. It is not difficult to separate television, in its earliest stages, from phototelegraphy. 4. The means of transmitting still pictures and moving pictures were discovered. 5. There was great rivalry between systems, but there is no controversy about contributions and priorities. 6. The decisive transformation of industrial production created new needs and possibilities.
- Answer the questions on paragraph 1:
- Has television altered our world? 2. Did the invention of television depend on a complex of inventions and developments in other fields of science? 3. Television has developed as a specific technological enterprise, hasnt it?
- Find the information dealing with scientists contribution to the development of television. Say it to your group-mate.
- Make an outline of the article.
- Speak about the history of television.