You Can Win in Bangla.pdf

12. A Trade Fair 

(a) What do you mean by a trade fair?
(b) Why is a trade fair organized?
(c) In Bangladesh where is a trade fair normally arranged?
(d) How is the fair arranged? (e) What things are found in a trade fair?

Click here to download the book

A trade fair is a fair for the display of industrial goods to the foreign buyers to get them acquainted with the exportable items of the country. By arranging trade fair we can make people aware of the market price. We can inform the customers about the quality of the product. In a trade fair a lot of companies take active part. In our country every year we arrange a lot of trade fairs. The government organizes an international trade fair every year in Sher-e-Bangla Nagar. A trade fair gives immense pleasure and opportunity to the customers. So it cannot be organized by an individual. It is normally held once a year. A great publicity is done for this purpose. And this publicity is made through advertisement in the national and international dailies to draw the attention of the industrialists and producers. The host country also advises friendly countries to install stalls in trade fair to display their exportable goods to the importers of the host country. As a trade fair gives scope to a country to display her products, friendly countries gladly respond to the call of the host countries. There are also arrangements for recreation, food etc, for the visitors. Thus a trade fair is very much useful. A host country can know the other parts of the globe through a trade fair. A trade fair should be held every year to encourage importers of foreign countries to import goods from our country. The day is no more so far when we shall be able to import necessary goods keeping the balance of trade in our favour.

Read More

Osomapto Attojiboni by Seikh Mujibur Rahaman.

Lesson 1 : Handy Input Devices

1.1. Learning Objectives
On completion of this lesson you will be able to describe:
 Different handy input devices
 Working principle of different handy input devices.

Click here to download the book. 

1.2. Introduction

Input devices get input from the external world to the computer. The input devices, which get input from the motion of the user’s hand, are known as handy input devices. Keyboard, light pen, digitizer, mouse, joystick and trackball, touch screen etc. are handy input devices. 1.3. Keyboard

The most common of all input devices is the keyboard. Several versions of keyboards are available. The best and most expensive of these is the full-stroke keyboard. This is ideal for word processing and other volume data and program entry activities.

Some popular microcomputers offer enhanced keyboard for easy entry of numbers. This is accomplished with a smaller group of keys known as numeric keypad at the right of the keyboard. These keys generally consist of the digits, a decimal point, a negative sign, and an ENTER key. This type of keyboard is ideal for accounting operations, which require a large volume of numbers

to be entered.

Keyboards generally utilize integrated circuits to perform essential functions, such as determining the combination of l s and Os, or binary code. To send to thc CPU, corresponding to each key depressed, switching between shifted and non shifted keys, repeating a key code if a key is held down for a prolonged period of time, and temporarily storing or "buffering" input when keys are typed too fast.

The keyboard arrangement provided as standard on most keyboards is the QWERTY arrangement. This arrangement was chosen to slow expert typists, since those who typed too fast would cause the keys on a mechanical typewriter to jam. Slowing down the typist was accomplished by scattering the most used around the keyboard, making frequently used combinations of letters awkward and slower to type. This QWERTY keyboard arrangement has been used for nearly a century.

Read More

Class Eight Math Full Solution. pdf

4.5. BIOS Initialization Process 

There are five steps to the BIOS initialization process:
 Test some low memory.
 Scan for other BIOS.
 Yield to other BIOS,
 Inventory the system.
 Test the system.

Click here to download the book.

4.5.1. Test Low Memory 

In order for the BIOS to function, it needs some RAM to work with. So for most BIOS, one of the first things that get done is to test the bottom part of the system's RAM. Now, if that test crashes, then most BIOS can’t recover. 

4.5.2. Scan for Other BIOS 

The BIOS in your PC can't support every possible piece of hardware-LAN boards, unusual video hoards, you name it-and so the important functions of inventory and initialization have to go somewhere else. That is why many add-on boards have some ROM on them, as you may have noticed when installing boards. What you may not know is that those ROM contain some initialization code for those boards. For example, a hard disk controller ROM might do a quick read of the hard disk-kind of an "are you there?" test. A video board might test the memory on the video board. The main system BIOS allows the add-on boards to do their inventory and initialization first. Now, before that can happen, the main system BIOS must find those BIOS. 

4.5.3. Yield to Other BIOS 

Once it has found BIOS on the add-on board, the main system BIOS passes control to that BIOS so that it can do whatever inventory and initialization the add-on BIOS requires. The main system BIOS allows every add-on card's BIOS to initialize itself before doing its own inventory and initialization. Notice what that means: the software contained in the ROM on an add-in board gets to run before the system BIOS, and it also runs certainly before DOS gets loaded-we haven't gotten near to loading DOS yet. For an example, consider a VGA board. It has a BIOS chip on it, one that contains a setup routine. That setup routine announces that the board is up and ready by putting a copyright notice on the screen. 

4.5.4. Inventory and Test the System 
Once all of the add-in ROMs have gotten their time, and assuming that their programs ran properly and returned control to the main system BIOS, then the main system BIOS will now inventory the items that it will control, items that will vary from system to system. At minimum, one of the items that the system BIOS must inventory and initialize is the system memory. What does "inventory and initialize" mean here? You have seen at least one example of it -the memory test. Ever notice the quick flash of the drive lights on the floppy and hard disk drives? That's the inventorying of the storage devices. 

4.5.5. Loading the Operating System 
After the BIOS initialization process the microcomputer system is prepared to load the operating system. At first the BIOS loads a portion of the operating system then this loaded potion of operating system starts loading its remaining portion.

Read More