It stores data when running applications Data in the chip can be altered It is non-volatile chip It stores configuration data for a computer system

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1 S3E MYE MARKING SCHEME 1. Any one from: a) Concept Keyboard b) Magnetic Ink Character Reader (MICR) c) Pressure Sensor d) Plotter e) Buzzer 2. One mark for each answer. Max two marks for all correct answers. Statements Tick It stores data when running applications Data in the chip can be altered It is non-volatile chip It stores configuration data for a computer system 3. a) Dot Matrix Printer b) Any one from: because dot matrix printers can be used in dusty, dirty or moist atmospheres as in greenhouse because the running cost are very cheap when we use dot matrix printer Unlike laser printers, dot matrix printers don t produce ozone and volatile organic compounds which can cause health problems. because dot matrix printers can do long print jobs using continuous stationery (e.g. long reams of perforated paper) Because the print quality of computer reading is not really a matter as long as it still readable. 4. Any two from 1) SSD has much faster data access time than HDD 2) SSD consume less power than HDD 3) SSD is extremely more robust than HDD 4) SSD has no moving part so it is more shock resistance than HDD 5) SSD is thinner than HDD, so SSD is more lightweight 6) SSD produces less noise than HDD because there is no moving part. 5. One mark for every correct answer: (a) Magnetic Tape (b) Fixed Hard Disk Drive (HDD) (c) Dongle (d) Flash Memory Card (e) DVD-ROM This marking scheme consists of 10 printed pages.

2 2 6. Model Reason Modeling Bridge Loading Can try out different scenarios in the computer model [1] Pilot Training Cost of building the real thing is too expensive [1] Space Exploration It is almost impossible to do the task for real [1] Environmental Modeling Some situations are too dangerous to humans [1] Nuclear Reactor Model Take too long to get the results back from real thing [1] 7. One mark for every correct answer: (a) Any one from: hub, switch, Access Point, router (b) Any one from: Router, Modem (c) Bridge, Router (d) Instant Messaging or (e) Web Browser (f) Internet Service Provider (ISP) 8. a. Any one from: 1. The robot is programmed with a sequence of instructions which allow it to carry out the series of tasks (e.g. spraying paint onto car body) 2. Alternatively, a human operator manually carries out the series of tasks; this can be done in two ways The robot arm is guided by a worker when doing the tasks; The worker straps sensors to his own arm and do the tasks; Each movement of the arm is stored as an instruction in the computer. b. 1. Robots can work in harmful environments 2. Higher productivity because don t need holiday 3. Greater consistency e.g. every car coming off a production line is identical 4. Robots can do boring, repetitive tasks leaving humans free to do other more skilled works 5. Robots don t complaint and only follow instructions 6. Because robots are independent of skills base, factory can be moved anywhere. c. 1. Robots find it difficult to do unusual tasks (lack of common senses) 2. Robots can cause unemployment because it replaces skilled labour 3. By using robots, factory can be moved anywhere, it can lead to unemployment. 4. Since robots do some repetitive tasks, there is a risk of losing certain skills e.g. welding. 5. Robots can t do jobs related to creativity e.g. designing jewelry/cars, aero modeling, etc. 6. Robots only do a certain task, so it requires a specialist to program robots to do new task.

3 9. a. Give two differences between flyers and posters. 1. Posters are bigger than flyers, so posters more eye catching 3 2. Posters are placed in a strategic position outdoor such as on building, advertising hoarding or billboard while flyers are sent out to household in certain area or handed out inside magazine 3. People tend to throw away flyers if it is not eye catching, but poster very difficult to miss because of its large size and posted on the way to work/outdoor. 4. Since posters posted on outdoor, posters are subject to weather conditions, so only have limited life time while flyers are not subject to weather conditions. 5. Flyers can be kept for further reading, posters can t be kept 6. Cost of displaying posters is more expensive than cost of distributing flyers 7. Flyers can be printed in braille so blind people can still read the advertisement, while posters can t b. Advantages of using websites to advertise 1. Sound / video / animation can be added into websites 2. Link to other websites / hyperlinks can be used 3. Can be accessed anywhere by the uses of hotspot 4. Navigation aids in websites leads to more information can be displayed 5. Hit counters to see how many people have visited the websites 6. Can be seen by a global audience 7. Unlike flyers and posters, websites can t be defaced or thrown away 8. It is much easier to change/update a website because there is no need to do a reprint and then distribute the new version. Disadvantages of using websites to advertise 1. Websites can be hacked into and modified 2. Websites can be infected with viruses 3. Risk of potential pharming (customers go to undesirable websites), so can lead to distrust from customers 4. Need a computer system and internet to access the websites 5. The cost of maintaining a website can be expensive because need specialists i.e. webmasters, web designers, programmers, network security experts, etc. 6. Because a website system is a global system, it is more difficult to target the correct audience using website advertising. c. Give two advantages paper-based presentations have over multimedia presentations. 1. Disable people don t have to go to venue to see the presentation 2. It is possible to print out paper-based presentation in braille for the benefit of blind people 3. The recipients can kept the paper-based presentation and read it at any time they want 4. The recipients have a permanent copy which they can refer to at any time they want

4 4 d. Usually in flyers, the company will include their business cards and letterheads. Give two reasons why it is important for the company to include their business cards and letterheads. 1. If the recipients want to order the products/ask questions, they can contact the company through the business cards because business cards can acts as personal contact 2. By including the letterhead, it gives a degree of credibility to the company (professionalism) 3. It can be used as brand / company awareness as it advertises company by using the same designs on all flyers. 4. It helps if there are any legal actions taken, legitimate documents using company letterhead is regarded as proof of actual communication 5. It helps to make company stand out and also good for advertising the company 6. Can give a degree of confidence to potential customers, so can make the company appear larger than it is 10. a. (i) Give two sensors used in measuring a patient s vital signs in a hospital. 1. Temperature sensor to measure body temperature 2. Pressure sensor to measure blood pressure 3. Motion sensor to measure heart beat 4. Oxygen level sensor to measure oxygen level in patient s blood (ii) Give one output device used in measuring a patient s vital signs in a hospital. Any one from: 1. Buzzer for alarm 2. LED / LCD Screen to display graph 3. Printer to print out the measurement result (iii) Describe how computer works to measure a patient s vital signs in a hospital. 1. Sensors read patient s key vital signs and send the data to microprocessor Any three from: 2. The computer compares the data from the sensors with the preset values stored in memory (these will be input by the doctor / nurse for particular patient) 3. Alarm/buzzer is activated if any of the reading data outside acceptable preset values 4. The result are output on a screen in the form of graphs or numerical data 5. The system continues to measure the patient s vital signs until the computer is off.

5 (iv) Give two advantages of using computer to measure a patient s vital sign 1. The computer would never forget to take readings 5 2. The computer s response time to warn about changes is much faster than a nurse 3. Doctors/nurses can do other tasks whilst the measurements are taken automatically 4. Computer gives 24-hours cover every day without break 5. Computer s reading tend to be more accurate 6. Readings can be taken more frequently if done by a computer and sensors 7. Computer can produce graph automatically for analysis of the results 8. Computer can keep the records of the readings for further research/analysis 9. There is a potential cost saving as fewer staffs are needed because the measurement is now done by computer. (v) Give two disadvantages of using computer to measure a patient s vital signs in a hospital. 1. The computer is unable to respond to unusual circumstances 2. Computer equipment and measuring software can be expensive to purchase and set up in the first place 3. If the computer malfunction (infected by viruses) or if there is a power cut, then the computer cannot be used (vi) Other than measuring a patient s vital signs in a hospital, give another example of measurement applications. Any one from: 1. Weather stations 2. Scientific experiments (i.e. taking temperature measurement) 3. Pollution monitoring in a river 4. Burglar alarm system b (i) Describe how computer works to control the chemical process. Any four from: 1. Temperature and ph sensors read data from the chemical process in analogue form 2. This data is then converted into digital using an ADC and then sent to the computer 3. The computer compares the incoming data with the preset value stored in memory: a. If the read temperature is less than 200 O C, a signal is sent to switch on heater If the read temperature is more than 300 O C, a signal is sent to switch off heater b. If the read ph is greater than 7, a signal is sent to open valves and add acid If the read ph is not greater than 7, a signal is sent to close valves 4. The computer signal will be changed into analogue signals using a DAC so that it can control the heaters and valves.

6 (ii) 6 Other than chemical process control, give another example of measurement applications. Any one from: 1. Automatic washing machine 2. Automatic ovens / cookers / microwave 3. Central heating system 4. Greenhouse / Glasshouse environment control 11. Incorrect Steps Marks steps steps steps 1 7 steps 0 Statements for Withdrawing Money from ATM Step Customer puts card into ATM, then customer types in the PIN 1 If they are the same the customer is asked which service is required 3 The customer s account is checked to see if it has sufficient funds 6 The amount is checked against the card limit 7 The typed PIN is compared with the PIN stored in the bank 2 The customer selects required service (cash) 4 If there are sufficient funds and the amount is within the card limit, then the required notes are issued. 8 The customer is asked how much money they want to withdraw Incorrect Steps Marks steps steps 1 6 steps 0 LEFT 90 REPEAT 6 RIGHT 60 BACKWARD 100 REPEAT 3 RIGHT 120

7 13. a. Give two advantages biometric data (fingerprint) has over the ID Card with a magnetic stripe Fingerprints are unique, so it will give more accurate data and improved security because it would be impossible for a student to sign in pretending to be someone else. With magnetic stripe cards, a student could give his card to a friend and ask them to sign in for him 2. Fingerprints are part of students, so can t be lost/forget to bring. But ID Cards could easily be lost / forget to bring 3. Fingerprints are not affected by strong magnetic fields, but ID Cards could be affected by strong magnetic field. 4. More difficult to copy/clone a fingerprint than ID Cards b. Give two advantages ID Card with a magnetic stripe has over the biometric data (fingerprint). 1. It will be less time consumes to print student ID Cards compare to collect the initial fingerprints of students. 2. Magnetic stripe readers is cheaper than fingerprints readers 3. ID Cards can be added with GPS tracking system, so can know the exact location of student 4. By showing ID Cards, the security guards can easily verify that the student is an active student, not an intruder. 14. Incorrect Marks steps steps steps steps 1 10 steps 0 Statements for Online Booking Systems The customers open the webpage 1 The customers choose the departure and destination location, the date and time of flights, the number of passengers, and personal details of each passenger If the number of passengers exceed the available seats, then inform the customers to choose another flight Step 2 3 The order details are shown on the screen 7 Customers confirm the order and type in the customer details (name, address, , etc) 8 Customers choose payment method and make the payment 9 If the payment successful, e-ticket will be sent to customers as a proof of purchase. Computer displays the available seats, together with the seating arrangement in the plane The customers select the seating positions as many as the number of passengers they ve entered Computer marks the seats as booked to prevent double booking and produces the total payment The database is then updated with the transaction. 11

8 8 15. a. Give one activity that you can do in online shopping but you cannot do in a shop. Any one from: Can shop anytime 24/7 even if the shops in the city are already closed. Can do shopping without needed to queue / travel to the shops in the city. b. Give one activity that you cannot do in online shopping but you can do in a shop. Any one from: Can t feel/touch/try the items displayed on the website Can t access the website if don t have computer system c. Give one activity that you can do in online banking but you cannot do in a bank. Any one from: Can do transactions (e.g. paying bills) without needed to queue / travel to the bank. Can do banking 24/7, even if the banks in the city are already closed. d. Give one activity that you cannot do in online banking but you can do in a bank. Any one from: Can t deposit / withdraw cash using online banking Can t access the website if don t have computer system 16. a. Describe how GPS systems know the exact location of the vehicles. Three mark if all steps are correct, two mark if missing one or two steps from: 1. Satellites in outer space transmit signals to the GPS device in the vehicles. 2. GPS device in vehicles (e.g. car, airplane or ship) receive and interpret these signals. 3. The location depends on very accurate timing (atomic clocks are used because of their accuracy to within a fraction of a second per day.) 4. Each satellite transmits data indicating its position and time. 5. GPS device in the vehicles calculates the location based on at least 3 satellites or more by using a method called trilateration. 6. GPS device combines the satellite information with the mapping information to tell us the exact location of the vehicles b. Give two advantages of using the satellite navigation system for the driver. 1. Safer for the driver because driver does not need to read maps, so it allows driver to concentrate on driving 2. Can give useful information such as location of gas station, speeding camera, traffic congestion 3. Can find shortest/fastest route 4. GPS systems can estimate the time of arrival, so the driver can arrange the schedule. c. Give two problems that can occur while the driver is using the satellite navigation system. 1. If maps are not updated, it can give us incorrect directions. 2. Satellite signal loss can cause problems / Potential interferences from external sources 3. Errors in start/end point keyed in the system 4. Sometime road closures due to accidents or road constructions can cause problem

9 9 17. (a) Incorrect Steps Marks steps 1 4 steps 0 Statements for How Expert System Works in Oil and Mineral Prospecting Step Questions are asked about geological profiles 2 The system suggests the probability of finding oil and mineral, makes predictions about geological deposits above the soils, etc. An interactive user screen appears 1 Answers to the questions about geological profiles are typed in using keyboard 3 The inference engine compares and searches the match answers in knowledge base using the rules base 5 4 (b) Incorrect Steps Marks steps 1 4 steps 0 Statements for How to Create an Expert System Step Experts are interviewed about how effective is the expert system before it published 4 Useful data and information is collected from interview with the experts in the field 1 A knowledge base, rules base, inference engine, and user interface (input screen & output format) is designed and created. The expert system is tested against known conditions and scenarios. 3 2 (c) Other than reduce time taken to solve problems, give one advantage of expert system. Any one from: 1. Expert systems provide consistent answers and not affected by emotional reasoning 2. Expert systems never forget to ask a question when determining the logic 3. Expert systems indicate the probability of the given solution being accurate / correct 4. The potential of saving money exists since there is less need for specialists / experts 5. Allows areas of the world access to expertise which they couldn t afford (d) Other than expensive, give one disadvantage of expert system. Any one from: 1. Expert systems tend to lack of common sense in some of the decision making processes 2. Error in knowledge base can lead to incorrect decisions being made 3. Need considerable training to ensure the system is used correctly by the operators (e) Other than oil and mineral prospecting, give one example of expert systems. Any one from: 1. Diagnosing a person s illness 2. diagnostics (finding faults in car engine, on circuit board, etc) 3. tax and financial calculations 4. strategy games (e.g. chess) 5. identifications of plants, animals, and chemical compounds 6. road scheduling for delivery vehicles.

10 a. A high school student who wants to apply as cashier. The suitable working pattern: any one from: Part-time Working Reason: any one from: A school student cannot work 40 hours a week, so part time will be suitable. As a part time worker, the student will have less working hour and have a fixed schedule to follow, so it will be easier for the student to manage his/her time. b. A tax consultant who wants to apply as financial consultant and requests to manage his own working hour. The suitable working pattern: any one from: Flexible Working Reason: any one from: Because with flexible working, the tax consultant can manage his own working hour. c. A girl who wants to apply as call centre agent. The suitable working pattern: any one from: Job Sharing Reason: any one from: She cannot work for 24 hours, so she has to share the load of the jobs. d. An experienced marketing staff who wants to apply as marketing manager and requests to have holiday every Friday, Saturday and Sunday. The suitable working pattern: any one from: Compressed Hours Reason: any one from: Because he wants to have holiday every Friday, Saturday and Sunday, so to fulfill 40 hours, he has to work longer on the other day.