english

Communications

Users often want to send messages from one network to another or to computers at the other side of the world. This can be done using a variety of communications links. Normal copper telephone wires can be used over short distances but shielded cable called coaxial cable or coax can be used for longer distances. However.coax has largely been replaced by even faster cable known as fibre optics or fibre optic cable. (Note that the American spelling of fibre is fiber.) Fibre optic cable uses glass fibres to conduct a beam of laser light. To transmit signals long distances around the world satellites are often used. The signal is transmitted and received by earth-satellite stations positioned at suitable locations over the earth's surface. Microwave transmissions are another means of transmitting signals from one microwave station to another.

An increasingly popular way of communicating using computers is voicemail. In this system, spoken messages are sent to a server computer where they are stored in areas called voice mailboxes. When the user connects to their mailbox they can listen to the stored messages.

Video conferencing is a more advanced form of communication by computer, which enables meetings to take place over long distances. Video cameras are used at each end of the communications link so that the participants can see and hear each other. The end of the link nearest a user is called Near End and the end of the link furthest from the user is called Far End. Each user has a keypad that enables them to control features of the system, for example to make or end a call, adjust the sound volume, and zoom the camera in to get close-up views, or zoom it back for a broader perspective. An additional display feature, called picture-in-picture, allows one image to be displayed inside another image.

When a piece of text is scanned using a scanner input device, an image of the text is input to the computer and displayed on the screen. It is not possible to change or edit the displayed text using a word processor, however, because the image is graphical, not digital. An optical character recognition (OCR) program must be used to convert the text image into digital text characters that can be edited. To identify a scanned text character, the software compares the character image to stored data about the shape of standard characters. It is easier for the OCR software to recognize the scanned characters if they are printed using block capitals and are not too small If a text is written in 'joined-up' writing, it is more difficult for the OCR to identify because there are extra lines and loops between the letters.

Objectives

By the end of this unit, students should be better at listening and reading for detailed information explaining rules orally.

They should be able to describe procedures using the present passive.

They should know and be able to use these words: voicemail, video conferencing, telephone lines, fibre optic cable, microwave station, earth satellite, relay, send, transmit.

Tuning in

Task 1

Before students look at the task, very briefly elicit some ideas from the class about the ways in which the San Francisco and Georgia departments could communicate and share information. Then ask them to work individually or in pairs to match the list of items a-e with the diagram.

Key

1a,h 2b,g 3c,f 4d 5

eTask 2

Set a time limit and ask the students to work in pairs. They should try and write down as many organizations which use long-distance computer communications to exchange information as they can.

Key

Examples: airlines, news agencies, weather forecasting, shipping lines.

Listening

Task 3

Elicit from the class what voicemail is. Find out if anyone knows what analogue and digital signals are before you let students look them up in the Glossary. You may also need to pre-teach caller and recipient. Note that on the diagram, analogue signals are shown by sine waves, and digital signals by square waves. When they have completed the matching task, ask the students to write a simple description of how a voicemail system works using only the diagram.

Key

1b 2d 3a 4c

Task 4

This provides practice in listening for detailed information. Start by quickly revising telling the time, and give students some practice in reading times out loud, e.g. 8.15-eight-fifteen or a quarter past eight, 8.30-eight-thirty or half-past eight, 8.45 - eight-forty-five or a quarter to nine.

Make sure they have enough time to read the questions and that they understand the situation, e.g who is London and who is in Brussels, etc. before you play the recording.

Note that the message contains an email address. This topic is addressed in more detail in Unit 13, Task 9, but you might want to explain to your students, that the letters 'b,e' at the end of the address indicate Belgium.

Key

1. One (for sales)

2. 10.15 a.m.

3. there are no seats on the 8.30 flight so he won't be on time

4. by plane

5. 9.45 a.m.

6. 10.30 a.m.

7. 11.15 a.m. is possible if the traffic isn't bad but he makes the appointment for 11.30 a.m. to be safe

8. because after 8.30 a.m. he will be on his way to the airport (students will have to infer this from the information they are given)

Task 5

The diagram shows a page from Lenny's organizer on his PC - appointments are made by clicking on the 'pages' with the mouse and adding the details and times. Students will probably be able to identify the problem of the meeting time immediately. Let them listen to the recording again to work out the details.

Key

The 'problem' is that Lenny can't meet with John Bailes at 11.30 because he has another appointment at that time. In his message, John asks Lenny to email him by 8.30 if there is any problem. However, Lenny does not check his voicemail until 9.00.This is too late to contact John, who will already be on his way to the airport.

Reading

Task 6

Check how much the students know about video conferencing. Your college or university may have this facility. Explain that the diagram shows the control pad for a video conferencing system. Ask the class to predict what sort of controls such a system would need, and write their predictions on the board. Pre-teach Near End (the caller), Far End (the recipient), mute (silent, the microphone is switched off), and banner (screen message). Students can then read the text for the first time to check which of the controls they predicted are mentioned. On the second reading, they can scan the text to find the answers to questions 1 and 2.

Key

1. a puts Near End, Far End, or both on mute

b controls the zoom in and out of the Far End camera

с selects numbers from the speed dial list d ends the call

2. aA bF cG dJ

Language work

Refer the students to the diagram of the police network in Task 1. Elicit the first few steps in sending a request for a suspect's record from San Francisco to Savannah. Write these on the board in as simple terms as possible.

1. A police officer requests a record.

2. His or her computer sends the message to a microwave station.

3. The station transmits the request to the nearest satellite.

Ask the class to identify the action (the verb) in each step. Underline this. Explain that often when we are describing a process the action is more important than the person or thing doing the action. Rub out the agent in each step, and convert actions 2 and 2 into the Present passive.

1. A record is requested.

2. The message is sent to a microwave station.

Ask a student to change action 3 in the same way.

Elicit the formation of the structure: the verb to be in the present tense (is, are), plus the past participle of the main verb. Point out that the past participle is normally formed by adding the suffix ed to the infinitive, but that there are many irregular verbs which do not take this form, e.g. send/sent, and they should make an effort to learn common irregular past forms.

Task 7

This is probably best done as an individual written task.

Key

[send, relay, and transmit are almost interchangeable in many contexts in this exercise) 1 are requested 2 is sent 3 is relayed 4 is transmitted

5 is transmitted 6 is relayed 7 is sent

Task 8

Using the information about San Francisco/Savannah communications at the beginning of this unit, the students should now be able to work together and discuss how records are sent. Do the activity orally first, eliciting the steps from the class. Then ask students to write their own descriptions of the process.

Problem-solving

Task 9

Set a short time limit for the students to write down, in pairs, as many links as they can think of.

Key (other answers are possible)

World Wide Web-to display texts, diagrams, and tasks

email - for student and teachers to communicate with each other

video conferencing - for live lectures, tutorials, and discussions

FTP (file transfer protocol) - for transferring or downloading files

Ask some pairs to talk through their descriptions and invite comment from the class.

Speaking

Task 10

This task focuses on some of the problems of optical character recognition, for example when computers are used to process handwritten cheques. Students can revise ways of giving advice (See Unit 7). For example: You should make the letters big. They're too smdll. You should use simple shapes. You shouldn't link characters.

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