酷兔英语
第14课听力
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  UNIT 14
Information Systems Today
Information technology is important and indispensable
to the life of human beings.
Transmission, recording or memory
and processing of information
are three essential process of information.
Virtually, the information technology
has been changing everyday.
The basic challenge of the coming decade
is how to make the already available technologies
as useful and friendly to a user as the telephone
or television set is to the common man.
Computers are a major segment of the new information technologies.
The constant growth of semiconductor technology
and the proliferation of the semiconductor memory devices
has brought possibilities that you use personal computers
to do anything you want to,
for instance, record a message and phone back an answer.
With the help of satellite communication,
the transmission of data has become very fast.
The data can be telexed;
the voice over a telephone can be transmitted on local,
national and international network.
The transmission of images through technology,
that's via a TV, is again going to be a major challenge,
as how to combine all these three components
of information technology into one.
It will bring about various problems.
The first is the privacy that goes with it.
For further addition to the impact of communication,
one can switch over from voices to images and data,
depending on an individual's need.
It is major challenge before the society at large
and the library professionals
as how to compress a library into a computer.
Moreover, on the user's part it is not easy
to sit at a terminal and read.
Basically some psychological
and social changes especially exert a subtle influence
on the minds of the young children,
so that they grow up with the habit of reading
on a computer screen.
It is also a fact that a large number of computers
have been used as sophisticated typewriters.
If you ask somebody who is the actual user of the computer,
it is probably the secretary.
A lot of PCs have dust covers on them
and one cannot be sure how frequently they are removed.
It is a strange phenomenon that people
haven't come out of their"hangups".
The terminal or keyboard of a personal computer
is looked up as an extension of a sophisticated typewriter.
Also there is a conventional barrier in sitting
and typing out the matter, which needs to be overcome.
That's why the advertising expenditures
have to be toned down to a certain level of reality.
There is worldwide a competition
going on as to how quickly you can gather,
dispatch or transmit the information.
There has been a tremendous bombardment
of information from all sides.
As the demand grows from the public to share the information,
at the same time every section of the society
is demanding more and more its share of message that goes across.
Besides, the homes have been invaded
by the message of consumerisminformation about goods,
marketing, politics, etc.
The tender minds of children are gradually corroded
by all the matter.
It is going to be a long struggle to convert
all the paper knowledge into the electronic medium.
Moreover, if we want to solve the literacy problem,
the computers may help in selflearning.
The noble place of a teacher will be taken up
by a personal computer,
as whatever one will see on the screen will become a reality,
why should anyone go to one's parents or teachers
when the PC can provide answers to all your questions.
Already, the latest PC
is there in the market in the United States,
which can store all full encyclopedias in it,
even the whole library.
With the widespread of information,
the categorized structure of the organization breaks up.
There is no need of various layers of management
to perform the varied tasks that are easier to be done
by computers. During the last decade
there was an open declaration that one person
can manage a project or a company.
In the 70's there was the concept of controlling finance.
Today, the widespread of information through various media
has to be managed.
In the 1940's there used to be radio sets
that had vacuum tubes,
which have been replaced today by the integrated circuit.
A technological advancement is gauged
by the power it gives or the energy it consumes
and the cost that is involved.
The technology that was prevalent in the 1940's
used to be about 100 percent more expensive
and about 1 000 times energy consuming.
Electronics in turn has revolutionized
the computer industry today.
Today, in the field of digital communication,
there is digital transmission,
digital switching and signaling that is taking place.
The progress of the digital techniques mainly
depends on computer's development
and the progress of digital transmission systems
based on it have merged computer and communication.
It has made possible the realization
of the three basic functions,i.e.,the transmission,
memory and processing in a simple form and realization
of further advanced and more complicated systems.
This progress has given us many useful means
to better our social life and welfare.