Notes, abstracts, papers, exams and problems of Computers

1. Make quality #1

   Quality must be quantified and mechanisms put into place to motivate its achievement. Defining quality commensurate with the project at hand is important but is not easily done at the outset of a project.

2. Involve the customer

   Techniques that have been demonstrated to increase quality include involving the customer, prototyping, simplifying design, conducting inspections, and hiring the best people. This principle is mostly redundant.

3. Give products to customers early

   No matter how hard you try to learn users' needs during the requirements phase, the most effective way to determine real needs is to give users a product and let them play with it.

4. Determine the problem before writing the requirements

   When faced with what they believe is

1. Why Can IEEE 802.11 Transmit Further Than Bluetooth?

IEEE 802.11 (Wi-Fi) has a higher power output than Bluetooth.

2. Three Advantages of Wireless Over Wired Technology

• Anytime, anywhere connectivity
• Easy and inexpensive to install
• Ease of adding additional devices

3. Two Benefits of Wireless Networks Over Wired Networks

• Mobility
• Reduced installation time

4. Factors Affecting the Number of Access Points Needed

Three factors that affect the number of access points needed for wireless connectivity are:

• The size of the building
• The number of solid interior walls in the building
• The presence of microwave ovens in various offices

5. Why is Security Important in Wireless Networks?

Security is crucial because wireless networks broadcast data over a medium that

Relational Keys

The Open Systems Interconnection Model

The Open Systems Interconnection (OSI) model is an abstract, layered representation created as a reference for network protocol design. The OSI model divides the process of networking into different logical layers, each of which has unique functionality and to which specific services and protocols are assigned.

Application Layer

The application layer, the seventh layer, is the top layer of both the OSI and TCP/IP models.

Presentation Layer

The presentation layer has three main functions:

• Coding and data conversion of the application layer to ensure that data from the source device can be interpreted by the appropriate application on the target device.
• Compression of the data in a way that can be decompressed

Importing Bitmap Images into Fireworks

Defining the Canvas

The first step is defining the work area or canvas (remember to have the negative area visible). Then, select the import option from the File menu.

A window like the one below will open.

Locating and Selecting the Image

In the Look in option, you'll search the folder where your image is saved. In the Files of type menu, the formats that Fireworks recognizes are shown. Once you select the file, click Open.

Placing the Image

The following mark will be displayed on the canvas, which means Fireworks is ready to bring in the selected image.

Simply click with your mouse or try to trace the desired size of the image.

That way, the image will appear on the canvas.

Image Properties

This image's properties... Continue reading "Importing Bitmap Images into Fireworks: Supported Formats" »

Pascal Code Examples

1. String Search in Array

This program searches for a given name within an array of strings.

Program Pzim;
var
  vet1: array[1..10] of string;
  nome: string;
  i, j: integer;
begin
  j := 0;
  for i := 1 to 10 do
  begin
    write('Enter the names: ');
    readln(vet1[i]);
  end;
  write('Enter the name to be searched: ');
  readln(nome);
  for i := 1 to 10 do
  begin
    if (nome = vet1[i]) then
    begin
      writeln('FOUND');
      j := j + 1;
    end;
  end;
  if (j = 0) then
    writeln('NOT FOUND');
end.

2. Merging Two Arrays

This program merges two arrays (vet1 and vet2) into a third array (vetx).

Program Pzim;
var
  vet1: array[1..5] of integer;
  vet2: array[1..10] of integer;
  vetx: array[1..15] of integer;

a) Advantage of Interrupts for Peripheral Devices

Explain the advantage of using interrupts as a technique for handling peripheral devices and relate it to computer performance. (10)

Answer

Interrupts offer a significant advantage because the processor doesn't need to constantly poll peripherals to check for data readiness. Instead, the peripheral alerts the processor when it's ready. This allows the processor to focus on other tasks while waiting for the peripheral, thus increasing overall computer performance.

b) Multiple Choice Questions on Interrupts

With regard to interrupts, check only what is correct in the following statements. (8) Explain why the last statement has been marked as correct. (7) Total 15 points

1.

To be considered an interrupt,... Continue reading "Understanding Interrupts in Computer Systems" »