Notes, summaries, assignments, exams, and problems for Computers

Freeform Vector Drawing Tools

In the Toolbar, within the Vector group, you will find the tools that allow you to draw freely: the Line and Pen tools.

To use them, simply select the desired tool from the Toolbar and move the mouse to the work area. Click the mouse where you wish to start and keep the button pressed until you reach the end point.

The Line Tool

The line is the simplest vector element, as it is composed of only two points and the line that connects them.

With this tool, you can form different lines to create the desired figure. To deselect a line, click in the negative area of the document. To select it again, grab the Pointer Tool from the Select group in the Toolbar.

Using the Properties Inspector

Always remember to observe the Properties

PC Hardware: Essential Components

Hardware refers to the set of physical elements, machinery, and components (such as the microprocessor, monitor, and keyboard) that constitute a personal computer (PC).

Software, on the other hand, consists of programs or applications, along with the data or information they process and store.

Understanding Data and Information

Data serves as the raw material input that computers transform into information. Processed data, or information, is the result, distinguished by its usefulness.

Key Characteristics of Useful Information:

• Relevant: The information is applicable to the current situation.
• Current: Information is updated and available precisely when needed.
• Accurate: Data entered into a computer and the resulting

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;

Database Components: Fields and Records

What is a Table?

Tables are the most fundamental objects in a database. They are used to store data organized into specific categories, structured in rows and columns.

What is a Field?

A field is the most basic unit of a database, representing a single piece of data. The names of fields cannot start with a space or special characters. A collection of fields for a single item is called a record.

Common Database Field Types

Different types of fields are used to store various kinds of data:

• Text: For alphanumeric characters, names, and descriptions up to 255 characters.
• Memo (Long Text): Used to store text longer than 255 characters with rich formatting options. It is ideal for notes, long explanations, and formatted

Bridges and Switches: Essential Network Elements

Bridges (Puentes) and Switches are network elements that possess control capabilities, storing and forwarding the frames they receive through their ports based on their content.

They are primarily used to interconnect similar or different Local Area Networks (LANs). A bridge isolates traffic between network segments.

For instance, if an Ethernet network needs to exceed 2.5 km in length, a bridge can be installed to segment the network. By assigning each segment a length not exceeding 2.5 km, a total network length of up to 5 km can be achieved.

OSI Layer 2 Operation

Bridges operate at OSI Layer 2 (Data Link Layer). Their basic unit of operation is the frame.

Phases in Frame Pathing Between Segments:

Robotics Fundamentals

• Machines involved in an assembly line, often appearing very smart, are known as industrial robots.
• The third generation of robots is characterized by using computers for control and having environmental perception through sensors.
• The word 'robot' originates from a term meaning servant or slave.
• Robotics is the branch of science and technology that studies the design and construction of machines capable of performing tasks typically done by humans or requiring intelligence.
• Light sensors and bumpers are devices that allow robots to locate themselves or objects in their environment.

Structured Programming and Algorithms

• Structured programming requires that all programs are built from three basic control structures: sequence, selection,

Chapter 7: Wireless LAN Fundamentals

802.11 Architecture and Operations

1. What are the main planes in a WLAN architecture?

• A) Management
• B) Control
• C) Data

2. Which plane handles signaling and coordination?

• A) Control

3. Which plane handles configuration and monitoring?

• B) Management

4. Which mechanisms are used for channel access in 802.11?

• A) CCA (Clear Channel Assessment)
• D) VCS (Virtual Carrier Sense)

5. What is the shortest interframe space in 802.11?

• C) SIFS (Short Interframe Space)

6. How many address fields are typically in an 802.11 frame?

• D) 4

7. What type of frame is sent by an AP in response to a client's probe request?

• A) Probe Response

8. What is used to derive the encryption keys in WEP?

• D) The WEP passphrase

9. What type of scanning involves listening

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" »

The Windows Control Panel: Your System's Command Center

The Windows Control Panel is your primary tool for configuring both the software and hardware installed on your computer. It organizes utilities into categories for easy access. Here's a breakdown of some key configuration options:

Add Hardware Wizard

This wizard guides you through installing new devices. Typically, you'll need the installation CD provided by the device manufacturer.

Add/Remove Programs (Programs and Features)

This section displays all programs installed on your computer. Select a program to uninstall it. To install a new program, run the installer file. To add or remove Windows features, click on "Turn Windows features on or off."

Network Connections (Network and Sharing Center)