Wednesday, October 31, 2012

What is Engineering Notation?

Definition : Engineering notation is a method of writing really big and really small numbers. In engineering notation, the exponent must always be a multiple of three so that it is equivalent to a value represented by a metric prefix.

Examples:

tera T 1,000,000,000,000 1012
giga G 1,000,000,000 109
mega M 1,000,000 106
kilo k 1,000 103
1 100
milli m 0.001 10¯3
micro ยต 0.000001 10¯6
nano n 0.000000001 10¯9
pico p 0.000000000001 10¯12


 
What is Scientific Notation ?

- Definition: Scientific Notation is based on powers of the base number 10.

Example:

The number 127,000,000,000 in scientific notation is written as :

127*10^11

the power 11= the amount of zeros.

other Examples:

 

Wednesday, October 24, 2012


Binary Conversions

1)       11011100   

1st -  00100011  ( flip the numbers)

2nd – 00100100   (Add plus 1 to the end of the numbers)

Oct – 44              

Hex – 24

Decimal  -36

2)      01101110

1st -  10010001

2nd - 10010010

Oct - 222

Hex - 92

Decimal - 146

 

3)      10110011

1st - 01001100

2nd -01001101

Oct - 115

Hex – 4D

Decimal – 77

 

4)      00010110

1st - 11101001

2nd - 11101010

Oct - 352

Hex - EA

Decimal - 234

 

5)      10101100

1st - 00110101

2nd – 00110110

Oct - 66

Hex - 36

Decimal - 54

 

 

Monday, October 22, 2012


Computer Structure: Fetch, Decode, Execute 




What is program counter :

          a register in the control unit of the CPU that is used to keep track of the address of the current or next instruction. Typically, the program counter is advanced to the next instruction, and then the current instruction is executed. Also known as a "sequence control register".

Steps:

1.    Fetch—Microprocessor gets a software instruction from memory telling it what to do with the data.

 
2.    Decode—Microprocessor determines what the instruction means.

 
3.    Execute—Microprocessor performs the instruction.

Layered Architecture

Each machine layer is an abstraction of the level below it.
The machine at each level executes its own instructions, calling upon machines at lower levels to perform tasks.



Unit Conversion

decimal
Octal
Hex
Binary
1
1
1
0001
2
2
2
0010
3
3
3
0011
4
4
4
0100
5
5
5
0101
6
6
6
0110
7
7
7
0111
8
10
8
1000
9
11
9
1001
10
12
A                    
1010
11
13
B
1011
12
14
C
1100
13
15
D
1101
14
16
E
1110

 

Tuesday, October 16, 2012

Hardware problem troubleshoot.

Problem: overheating: which is a common problem mostly happens with laptops.
Firstly it makes your computer perform very slowly.
Secondly blue screens will appear like this on the picture:


Thirdly computer will start restarting and shutting down.
It happens because the CPU becomes overheated so the computer protects the CPU by shutting down otherwise it will melt.

it also sometimes makes a physical damage to the case and even cause burn to the user if it touches the body directly, as you see below:




How to fix it :
1-      Make sure the fan cable is plugged on mother board.

2-      Clean the fan and make sure u use the thermal paste (cooling liquid) because sometime the fan is working well but it doesn't receive all the heat so the CPU still overheated.

thermal paste :very high heat conductive paste that is used between two objects
3-      Change fan.



Software troubleshooting:-

problem: The Nvidia graphic card performance is weak and not smooth after format, especially in video games. Also the screen resolution is low.



solution:
1)  Go to the nvidia official site. click on drivers and search for the driver that matches your graphic card.

2)  Download and install the graphics driver and restart your system. Running graphic intensive applications    should be smoother since the graphic card is up to date.