chapter5-8

Revision Questions sorted to Chapter 1 / 2 / 3 / 4 Stephen Doyle "Information Systems for You"

Algorithms / Programming / System Design

Explain the difference between a compiler and an interpreter. / / Give one example of the use of a program written in a low-level language.

Applications / Security / Social impacts

Some customers of a bank use electronic funds transfer (EFT) to pay for purchases. Explain one disadvantage of EFT to the customer and one advantage to the bank of this method of payment.

EFT is electronic (fund) money transfer. Customers could make use of a bankcard, either with magnetic strip or a Chip-card. / / Each customer needs to have a account number sometimes a password, called a PIN-code. Some cards require just your signature on the receipt (Credit cards) / / Disadvantage for customer: / - you can spend too much too easy / - if you loose it, big problems can arise! / - you might not know how much money you have left / / Advantage to the bank: / - always available to customers (24 hours a day) / - no queuing in the bank / - it will cost less and is very fast

Applications / Software / Input Devices

Staff at a bicycle factory use computer-aided-design and computer-aided manufacture (CAD/CAM) to design and make the parts for the bicycles. / / Describe two features of the CAD program that makes it suitable for designing the parts for the bicycles.

CAD is computer aided design. It allows to draw in 3D any part needed to construct a bicycle. In the old days they used blue prints (on paper). / / Advantages: / - you can magnify components (zoom in / out) / - you can scale / rotate / reshape / change / add patterns / - you can create a model / - it is very accurate / / CAM is computer aided manufacturing. The computer regulates the production process. Tulip builds in Rosmalen a factory using CAM, that makes PC's all automatically. The computers control the processing, have all the data concerned and necessary. /

Applications / Software / Spreadsheet / Wordprocessing / Database

What is software? / Give 3 examples of application software used in business and/or office.

Software is the (digital) data needed in any computer system. It stores all instructions (how to operate) and all necessary data (information needed to run a certain program) / / - Spreadsheet (Excel), used for doing calculations and producing charts / - Wordprocessor (Word, Wordperfect), allowing to produce letters etc. / - Database (Filemaker, DBase), allowing to store and retrieve large amounts of data / - E-Mail (Eudora, Compuserve), software allowing to send and retrieve electronic mail (e.g. via the Internet)

Control Systems / Applications

Plants grow in soil that needs to be damp. How could a computer system help to keep the soil damp? Explain the purpose of each hardware item you mention.

You will need to have a reliable, steady computer, which will be on-line 24 hours a day. It will measure the moisture with the help of a computer input device, a sensor. The sensor is in fact an analogue to digital converter (ADC), so the information (the data) will be inputted into the computers CPU. You will need probably several sensors in order to get sufficient data. The computer will hav a software program, that gives instructions what to do. In case the moisture is too low, the CPU will send a start signal to an output device, which will initiate e.g. an engine or pump, so water will be sprinkled onto the soil. If the moisture reaches a certain value (measured by the sensors) the CPU will send a stop signal to the (e.g.) pump. Very helpful would be a keyboard and monitor to change any settings, and a printer that can print out any mistakes and all the measured data of certain intervalls. /

Input Data

The data read from cheques and other transactions at a large bank is stored on magnetic tape. What type of file access must be used to access this data?

Only serial File Access can be used (read the records in a serial way, one after another in a row)

Input Data

Why are check-digits used?

It allows to check if input data was entered correctly. A check-digit can be attached to (e.g.) a barcode. If the scanning goes wrong (maybe the label is damaged or dirty) the check-digit check will cause the computer to display an error message (instead of accepting the wrong input data! -> think about the wrong price scanned at a supermarket!)

Input Data / Input Devices

The customer account number and branch code are printed on the bottom of bank's cheque. / / a) Name an item of data that must be typed in magnetic ink on each cheque before it is processed. / / b) Give one advantage of using magnetic ink character recognition as an input method to input the data on the cheques.

Input Devices / Input Data

A bar code reader is an input device which can read data presented in a machine readable form. Give 2 other methods of reading data automatically and give for each an example of an application.

Punch card reader - used in (old-fashioned) programming / MICR-reader - a magnetic ink reader, used for reading cheques in banks (old-fashioned) / Lightpen - used for recognizing input on a computer screen (e.g. architects) / Scanner combined with OCR - a scanner can be used to read documents, the OCR (optical character recognition software) will recognize the characters and convert the scanned image into readable text. / Mark sense reader OMR (scanner) - this input device will recognize marked (checked) boxes on pre-printed forms. These forms are mainly used for large data entries, such as multiple choice exam papers. Also to collect data (e.g. gas-meter) from different locations. / Chipcard reader - the Chipcard reader will recognize the data stored in the chip (in the memory). It can be used with modern telephones, so no cash money is necessary, since the amount available is stored on the card. / Magnetic card reader - the reader device will recognize the information stored on the magnetic stripe on the card. It is less reliable as the Chipcard, but cheaper to produce. It is very often used as an identification card for banks, shops etc. Cards could be used to receive money from ATM machines.

Input Devices / Input Data

What is OCR? Who would use it? What do you need?

Optical Character Recognition / / Postoffice reading the Postcode (ZIP) for automatic mail-sorting / / Hardware: a scanner / Software: an OCR program

Input Devices / Input Data

What is OMR? Who would use it? What do you need?

Optical MARK Recognition / / Marking of tests, where students fill in with a pencil the boxes (good for multiple choice!!) / / Hardware: a special OMR scanner / Software: an OMR recognition program

Input Devices / Input Data / Security

Give one example of the use of speech recognition devices. / / Give one reason why speech output may not be a sensible method of giving warning messages to drivers.

In an office, a doctor checking patients

Networking / Applications / Software / Database / Spreadsheet

The police need to keep files of wanted people to write accounts of interviews with suspects, to produce details of their expenses and to send messages to and receive messages from the other terminals on their network. / / List the four types of software that must be available on the network.

Software for files of wanted people: / / Software for accounts of interviews: /

Programming

Explain the relationship between a compiler, a source program and an object program

The source program (e.g. written in Pascal or C++) will be translated by the compiler into a machine readable code that can be used by the specific computer, the object code. / THe compiler translates all code in one go. (An interpreter translates line-by line)

Programming

Explain, using examples if appropriate. / data type

Programming

What is Assembler?

Assembly code is a low level programming language. Assembler contains instructions that are based on a specific CPU. / That means that there are several assembler versions, they are different for different CPU's (like Intel, Motorola etc.) / An Assembler is the compiler, that will translate the assembly language into machine code (binary code), so the program can run on the specific CPU (computer) / example: Store 4, Load 3, Add 4, Print 3 (the numbers determine the registers = storage places in the CPU)

Programming

What is Rogue Value?

It is an unusual value to show / reach the end of data input (in a program). / / For example when you would read records of customers, you could let the program stop if instead of a name the characters "######" will be read. It is quite normal that when programs run with a loop (iteration), they have such a rogue value to stop the loop.

Programming / Algorithms / Software

What is a compiler?

When a computer programmer writes a program, the programming language use has some resemblance to human speech&emdash;even we non-programmers can read some of the words, like 'if' and 'then' and 'do', almost look like real words. But a computer can't understand anything about a program written in a programming language, not even the plus signs. / In order to run that program, the programmer has to first convert it into computer-ese, known as machine code, using a special program called a compiler. Usually, the compiler produces an intermediate form of the program which is then converted (with other moduls as well) to the final, working form by a "linker," another special program. / As a verb, to compile a program is to convert it into machine code using a compiler.

Programming / Input Data / Security / System Design

What is Verification?

Check the data before you input it into the computersystem / / E.g: type the data twice and then compare the result. If it is not the same, repeat it all again! / / (Disadvantage: slow, expensive, time consuming!)

Programming / Software / Database

What data types can you mention?

Data can be classified according: / Alphanumerical data (all you can find e.g. at a keyboard) / - Characters (like used in the alphabet) / / Numerical data (all numbers, including decimal point, comma, arithmetic signs (+ * etc.) / - Integers (whole numbers) / - Real numbers (numbers with decimal value) / / - Boolean type (true/false values only)

Software

Explain three disadvantages of using integrated packages. /

1. Might be weaker in some parts as a sophisticated software program. / 2. Might be harder to get updates with features you want! / 3. You might miss some functions in the software, so you have to buy other software too!

Software / Hardware / Telecommunication

Analogue-to-digital conversion /

Software / Input Data / Output Data

What is a GUI?

A gui is a graphical user interface. The Apple Macintosh computer was the first computer who used a GUI. It makes the working with a computer system user-friendly and easier. Also Windows from Microsoft is using a GUI. The word interface stands for the way we can communicate with a system (Man-Computer interface) / / If you look at the operating system MS-DOS, it's know as a single command line interface. You will have to type commands like -> A:/dir in order to see what files there are on your floppy disk. / When you use a GUI, you will just click the icon of your floppy and you will see the contents (again listed with small icons in a new window). / / Computers will use (e.g.): / - little icons and pictures (representing programs, or items like a bin or trash) / - menus. We know drop-down, pull-up menues etc. / - make use of colours. Colours can identify different items (like programs) / - makes use of sound (you can e.g. hear the mouseclick) / - pointers (usually in combination with a mouse)

Software / Input Devices / Output Devices

What is a multimedia system?

A system that makes use of: / - sound / - CD-ROM / - graphics display / - often also a GUI operating system / - capable of showing video on the screen / / Often used for playing games, but also great for browsing e.g. encyclopedias!

System Design / Programming / Applications

A company needs a new software application for its business. / It is decided that a programmer should not be employed and that software packages with a graphical user interface should be purchased. / / (i) Give one advantage of buying software packages instead of writing a program. / (ii) Give one advantage of a graphical user interface. /

Validation / Input Data

Mention 3 different validation checks which can be used on an order code number like: 0947251839

Length check - all code numbers should have 10 digits (for example also valid for a dutch telephone number) / Range check - the order number should be in between 1 and 999999999 / Availability check - check if the order number is available in the database system / Check-sum (Check Digit) - check (calculate) the total of the orders by hand and compare with the computers calculation / Data-Type-Check -> see if they are all numbers

Validation / Input Data

What is a check-sum?

Checksum is a technique used by some communications protocols to check for errors in the information that has been transmitted over the wires. The numbers of bits, or electronic units, of information, is added up (summed) before it is sent. Then the protocol sends that sum along with the data. When the receiving computer gets the data, it counts the bits and checks it with the sum that was sent along. If the two sums don't match, there was probably an error in the transmission (meaning the data transmission will have to be done one more time).

Algorithms / Programming / System Design	Explain the difference between a compiler and an interpreter. / / Give one example of the use of a program written in a low-level language.
Applications / Security / Social impacts	Some customers of a bank use electronic funds transfer (EFT) to pay for purchases. Explain one disadvantage of EFT to the customer and one advantage to the bank of this method of payment.	EFT is electronic (fund) money transfer. Customers could make use of a bankcard, either with magnetic strip or a Chip-card. / / Each customer needs to have a account number sometimes a password, called a PIN-code. Some cards require just your signature on the receipt (Credit cards) / / Disadvantage for customer: / - you can spend too much too easy / - if you loose it, big problems can arise! / - you might not know how much money you have left / / Advantage to the bank: / - always available to customers (24 hours a day) / - no queuing in the bank / - it will cost less and is very fast
Applications / Software / Input Devices	Staff at a bicycle factory use computer-aided-design and computer-aided manufacture (CAD/CAM) to design and make the parts for the bicycles. / / Describe two features of the CAD program that makes it suitable for designing the parts for the bicycles.	CAD is computer aided design. It allows to draw in 3D any part needed to construct a bicycle. In the old days they used blue prints (on paper). / / Advantages: / - you can magnify components (zoom in / out) / - you can scale / rotate / reshape / change / add patterns / - you can create a model / - it is very accurate / / CAM is computer aided manufacturing. The computer regulates the production process. Tulip builds in Rosmalen a factory using CAM, that makes PC's all automatically. The computers control the processing, have all the data concerned and necessary. /
Applications / Software / Spreadsheet / Wordprocessing / Database	What is software? / Give 3 examples of application software used in business and/or office.	Software is the (digital) data needed in any computer system. It stores all instructions (how to operate) and all necessary data (information needed to run a certain program) / / - Spreadsheet (Excel), used for doing calculations and producing charts / - Wordprocessor (Word, Wordperfect), allowing to produce letters etc. / - Database (Filemaker, DBase), allowing to store and retrieve large amounts of data / - E-Mail (Eudora, Compuserve), software allowing to send and retrieve electronic mail (e.g. via the Internet)
Control Systems / Applications	Plants grow in soil that needs to be damp. How could a computer system help to keep the soil damp? Explain the purpose of each hardware item you mention.	You will need to have a reliable, steady computer, which will be on-line 24 hours a day. It will measure the moisture with the help of a computer input device, a sensor. The sensor is in fact an analogue to digital converter (ADC), so the information (the data) will be inputted into the computers CPU. You will need probably several sensors in order to get sufficient data. The computer will hav a software program, that gives instructions what to do. In case the moisture is too low, the CPU will send a start signal to an output device, which will initiate e.g. an engine or pump, so water will be sprinkled onto the soil. If the moisture reaches a certain value (measured by the sensors) the CPU will send a stop signal to the (e.g.) pump. Very helpful would be a keyboard and monitor to change any settings, and a printer that can print out any mistakes and all the measured data of certain intervalls. /
Input Data	The data read from cheques and other transactions at a large bank is stored on magnetic tape. What type of file access must be used to access this data?	Only serial File Access can be used (read the records in a serial way, one after another in a row)
Input Data	Why are check-digits used?	It allows to check if input data was entered correctly. A check-digit can be attached to (e.g.) a barcode. If the scanning goes wrong (maybe the label is damaged or dirty) the check-digit check will cause the computer to display an error message (instead of accepting the wrong input data! -> think about the wrong price scanned at a supermarket!)
Input Data / Input Devices	The customer account number and branch code are printed on the bottom of bank's cheque. / / a) Name an item of data that must be typed in magnetic ink on each cheque before it is processed. / / b) Give one advantage of using magnetic ink character recognition as an input method to input the data on the cheques.
Input Devices / Input Data	A bar code reader is an input device which can read data presented in a machine readable form. Give 2 other methods of reading data automatically and give for each an example of an application.	Punch card reader - used in (old-fashioned) programming / MICR-reader - a magnetic ink reader, used for reading cheques in banks (old-fashioned) / Lightpen - used for recognizing input on a computer screen (e.g. architects) / Scanner combined with OCR - a scanner can be used to read documents, the OCR (optical character recognition software) will recognize the characters and convert the scanned image into readable text. / Mark sense reader OMR (scanner) - this input device will recognize marked (checked) boxes on pre-printed forms. These forms are mainly used for large data entries, such as multiple choice exam papers. Also to collect data (e.g. gas-meter) from different locations. / Chipcard reader - the Chipcard reader will recognize the data stored in the chip (in the memory). It can be used with modern telephones, so no cash money is necessary, since the amount available is stored on the card. / Magnetic card reader - the reader device will recognize the information stored on the magnetic stripe on the card. It is less reliable as the Chipcard, but cheaper to produce. It is very often used as an identification card for banks, shops etc. Cards could be used to receive money from ATM machines.
Input Devices / Input Data	What is OCR? Who would use it? What do you need?	Optical Character Recognition / / Postoffice reading the Postcode (ZIP) for automatic mail-sorting / / Hardware: a scanner / Software: an OCR program
Input Devices / Input Data	What is OMR? Who would use it? What do you need?	Optical MARK Recognition / / Marking of tests, where students fill in with a pencil the boxes (good for multiple choice!!) / / Hardware: a special OMR scanner / Software: an OMR recognition program
Input Devices / Input Data / Security	Give one example of the use of speech recognition devices. / / Give one reason why speech output may not be a sensible method of giving warning messages to drivers.	In an office, a doctor checking patients
Networking / Applications / Software / Database / Spreadsheet	The police need to keep files of wanted people to write accounts of interviews with suspects, to produce details of their expenses and to send messages to and receive messages from the other terminals on their network. / / List the four types of software that must be available on the network.	Software for files of wanted people: / / Software for accounts of interviews: /
Programming	Explain the relationship between a compiler, a source program and an object program	The source program (e.g. written in Pascal or C++) will be translated by the compiler into a machine readable code that can be used by the specific computer, the object code. / THe compiler translates all code in one go. (An interpreter translates line-by line)
Programming	Explain, using examples if appropriate. / data type
Programming	What is Assembler?	Assembly code is a low level programming language. Assembler contains instructions that are based on a specific CPU. / That means that there are several assembler versions, they are different for different CPU's (like Intel, Motorola etc.) / An Assembler is the compiler, that will translate the assembly language into machine code (binary code), so the program can run on the specific CPU (computer) / example: Store 4, Load 3, Add 4, Print 3 (the numbers determine the registers = storage places in the CPU)
Programming	What is Rogue Value?	It is an unusual value to show / reach the end of data input (in a program). / / For example when you would read records of customers, you could let the program stop if instead of a name the characters "######" will be read. It is quite normal that when programs run with a loop (iteration), they have such a rogue value to stop the loop.
Programming / Algorithms / Software	What is a compiler?	When a computer programmer writes a program, the programming language use has some resemblance to human speech&emdash;even we non-programmers can read some of the words, like 'if' and 'then' and 'do', almost look like real words. But a computer can't understand anything about a program written in a programming language, not even the plus signs. / In order to run that program, the programmer has to first convert it into computer-ese, known as machine code, using a special program called a compiler. Usually, the compiler produces an intermediate form of the program which is then converted (with other moduls as well) to the final, working form by a "linker," another special program. / As a verb, to compile a program is to convert it into machine code using a compiler.
Programming / Input Data / Security / System Design	What is Verification?	Check the data before you input it into the computersystem / / E.g: type the data twice and then compare the result. If it is not the same, repeat it all again! / / (Disadvantage: slow, expensive, time consuming!)
Programming / Software / Database	What data types can you mention?	Data can be classified according: / Alphanumerical data (all you can find e.g. at a keyboard) / - Characters (like used in the alphabet) / / Numerical data (all numbers, including decimal point, comma, arithmetic signs (+ * etc.) / - Integers (whole numbers) / - Real numbers (numbers with decimal value) / / - Boolean type (true/false values only)
Software	Explain three disadvantages of using integrated packages. /	1. Might be weaker in some parts as a sophisticated software program. / 2. Might be harder to get updates with features you want! / 3. You might miss some functions in the software, so you have to buy other software too!
Software / Hardware / Telecommunication	Analogue-to-digital conversion /
Software / Input Data / Output Data	What is a GUI?	A gui is a graphical user interface. The Apple Macintosh computer was the first computer who used a GUI. It makes the working with a computer system user-friendly and easier. Also Windows from Microsoft is using a GUI. The word interface stands for the way we can communicate with a system (Man-Computer interface) / / If you look at the operating system MS-DOS, it's know as a single command line interface. You will have to type commands like -> A:/dir in order to see what files there are on your floppy disk. / When you use a GUI, you will just click the icon of your floppy and you will see the contents (again listed with small icons in a new window). / / Computers will use (e.g.): / - little icons and pictures (representing programs, or items like a bin or trash) / - menus. We know drop-down, pull-up menues etc. / - make use of colours. Colours can identify different items (like programs) / - makes use of sound (you can e.g. hear the mouseclick) / - pointers (usually in combination with a mouse)
Software / Input Devices / Output Devices	What is a multimedia system?	A system that makes use of: / - sound / - CD-ROM / - graphics display / - often also a GUI operating system / - capable of showing video on the screen / / Often used for playing games, but also great for browsing e.g. encyclopedias!
System Design / Programming / Applications	A company needs a new software application for its business. / It is decided that a programmer should not be employed and that software packages with a graphical user interface should be purchased. / / (i) Give one advantage of buying software packages instead of writing a program. / (ii) Give one advantage of a graphical user interface. /
Validation / Input Data	Mention 3 different validation checks which can be used on an order code number like: 0947251839	Length check - all code numbers should have 10 digits (for example also valid for a dutch telephone number) / Range check - the order number should be in between 1 and 999999999 / Availability check - check if the order number is available in the database system / Check-sum (Check Digit) - check (calculate) the total of the orders by hand and compare with the computers calculation / Data-Type-Check -> see if they are all numbers
Validation / Input Data	What is a check-sum?	Checksum is a technique used by some communications protocols to check for errors in the information that has been transmitted over the wires. The numbers of bits, or electronic units, of information, is added up (summed) before it is sent. Then the protocol sends that sum along with the data. When the receiving computer gets the data, it counts the bits and checks it with the sum that was sent along. If the two sums don't match, there was probably an error in the transmission (meaning the data transmission will have to be done one more time).