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Environment Protection Must Be Global



Television

The television set is evidently the most important and popular electronic product of all time. All homes in developed countries have one or more TV sets. But in 1939 at the World’s Fair in New York a tiny 9-by-12 inch box was the center of attention for hundreds of people. They were the first to see a television set in action. Within a few days the news of television spread throughout the world. A lot of people wanted to have a look at the new invention. Everyone was interested in it. But only few people owned television sets in the next few years. When World War II broke out electronic factories that began the TV production stopped, when the war was over, TV sets began coming off factory assembly lines. At present TV communication is provided with the help of a system of artificial earth satellites so that people living in different parts of the country and all over the world and in different time zones are able to watch the central TV programs. Nowadays many countries also have a cable TV, a system using wires for the transmission of TV programs. A new technical invention, colour TV, was rapidly replacing black-and-white TV. A few years ago it became evident that the next major advance for would be digital TV. In a digital system a signal is replaced by a digital code. By the end of 1980s TV has moved to a new and the most important stage in its development since the appearance of colour TV. Technically it is called high-definition TV or Hi-Vision. This is the much higher resolution TV of the 21st century. The engineering problem that has exited almost since the first days of TV may be solved now.

 

Electricity

It is impossible to imagine our civilization without electricity: economic and social progress will be turned to the past and our daily lives completely. Electrical power has become universal. Thousands of applications of electricity such as lighting, electrochemistry and electrometallurgy are longstanding and unquestionable. Other devices are based on specific properties of electricity: electrostatics in the case of photocopying machine and electromagnetism in the case of radar and television. The first industrial application was in the silver workshops in Paris. The generator-a new and compact source of electricity-was also developed there. The generator replaced the batteries and other devices that had been used before. Since the beginning of the 20th century the successful development of electricity has begun throughout the world. The consumption of electricity has doubled every ten years. One of the greatest advantages of electricity is that it is clean, easily-regulated and generates no by-product. Applications of electricity now cover all fields of human activity from house washing machines to the latest laser devices. Truly electricity provides mankind with the energy of the future.



 

Environment Protection Must Be Global

That the problem of pollution and ecology has become the most important one for mankind is evident to all. Air and water pollution by industry is now reaching tremendous proportions. In our era it is changing from a national to an interna­tional problem. However, our scientific knowledge and technological advance­ment make it possible to eliminate it if people use good will and make considerable investments for that purpose. At present scientists in industrially developed countries are working on the theory of interaction of all the atmospheric and oceanic global problem. Increasing growth of population, industrialization and the use of resources are slowly but surely changing the global climate and water balance. It is the joint effort of many scien­tists and special public organizations that can deal with the prob­lem and take necessary measures to protect the environment. It is still a big job and much remains to be done.





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