The Universal Product Code (UPC), often known as a bar
code, labels virtually every sold good. An
example of a
portion of the code is shown.
Here a sequence of black and white bars, each having width
, presents an 11-digit number
(consisting of decimal digits) that uniquely identifies theproduct. In retail stores, laser scanners read this code,
and after accessing a database of prices, enter the priceinto the cash register.
How many bars must be used to represent a single
digit?
A complication of the laser scanning system is that
the bar code must be read either forwards or backwards.Now how many bars are needed to represent each
digit?
What is the probability that the 11-digit code is
read correctly if the probability of reading a singlebit incorrectly is
?
How many error correcting bars would need to be
present so that any single bar error occurring in the11-digit code can be corrected?
Error correcting codes
A code maps pairs of information bits into codewords of
length 5 as follows.
Data
Codeword
00
00000
01
01101
10
10111
11
11010
What is this code's efficiency?
Find the generator matrix
and parity-check
matrix
for this code.
Give the decoding table for this code. How many
patterns of 1, 2, and 3 errors are correctlydecoded?
What is the block error
probability (the probability of any number of errors
occurring in the decoded codeword)?
Digital communication
A digital source produces sequences of nine letters with the following probabilities.
letter
a
b
c
d
e
f
g
h
i
probability
Find a Huffman code that compresses this source.
How does the resulting code compare with the best possible code?
A clever engineer proposes the following (6,3) code to correct errors after transmission through a digital channel.
What is the error correction capability of this code?
The channel's bit error probability is 1/8.
What kind of code should be used to transmit data over this channel?
Overly designed error correction codes
An Aggie engineer wants not only to have codewords for his
data, but also to hide the information from Rice engineers(no fear of the UT engineers). He decides to represent
3-bit data with 6-bit codewords in which none of the databits appear explicitly.
Find the generator matrix
and parity-check matrix
for this
code.
Find a
matrix that recovers the data bits from the
codeword.
What is the error correcting capability of the
code?
Error correction?
It is important to realize that when more transmission
errors than can be corrected, error correction algorithmsbelieve that a smaller number of errors have occurred and
correct accordingly. For example, consider a (7,4) Hammingcode having the generator matrix
This code corrects all single-bit error, but if a double bit error
occurs, it corrects using a single-bit error correction approach.
How many double-bit errors can occur in a
codeword?
For each double-bit error pattern, what is the
result of channel decoding? Express your result as abinary error sequence for the data bits.
Questions & Answers
Three charges q_{1}=+3\mu C, q_{2}=+6\mu C and q_{3}=+8\mu C are located at (2,0)m (0,0)m and (0,3) coordinates respectively. Find the magnitude and direction acted upon q_{2} by the two other charges.Draw the correct graphical illustration of the problem above showing the direction of all forces.
To solve this problem, we need to first find the net force acting on charge q_{2}. The magnitude of the force exerted by q_{1} on q_{2} is given by F=\frac{kq_{1}q_{2}}{r^{2}} where k is the Coulomb constant, q_{1} and q_{2} are the charges of the particles, and r is the distance between them.
Muhammed
What is the direction and net electric force on q_{1}= 5µC located at (0,4)r due to charges q_{2}=7mu located at (0,0)m and q_{3}=3\mu C located at (4,0)m?
Capacitor is a separation of opposite charges using an insulator of very small dimension between them. Capacitor is used for allowing an AC (alternating current) to pass while a DC (direct current) is blocked.
Gautam
A motor travelling at 72km/m on sighting a stop sign applying the breaks such that under constant deaccelerate in the meters of 50 metres what is the magnitude of the accelerate
velocity can be 72 km/h in question. 72 km/h=20 m/s, v^2=2.a.x , 20^2=2.a.50, a=4 m/s^2.
Mehmet
A boat travels due east at a speed of 40meter per seconds across a river flowing due south at 30meter per seconds. what is the resultant speed of the boat
which has a higher temperature, 1cup of boiling water or 1teapot of boiling water which can transfer more heat 1cup of boiling water or 1 teapot of boiling water explain your . answer
I believe temperature being an intensive property does not change for any amount of boiling water whereas heat being an extensive property changes with amount/size of the system.
Someone
Scratch that
Someone
temperature for any amount of water to boil at ntp is 100⁰C (it is a state function and and intensive property) and it depends both will give same amount of heat because the surface available for heat transfer is greater in case of the kettle as well as the heat stored in it but if you talk.....
Someone
about the amount of heat stored in the system then in that case since the mass of water in the kettle is greater so more energy is required to raise the temperature b/c more molecules of water are present in the kettle
pratica A on solution of hydro chloric acid,B is a solution containing 0.5000 mole ofsodium chlorid per dm³,put A in the burret and titrate 20.00 or 25.00cm³ portion of B using melting orange as the indicator. record the deside of your burret tabulate the burret reading and calculate the average volume of acid used?
No. According to Isac Newtons law. this two bodies maybe you and the wall beside you.
Attracting depends on the mass och each body and distance between them.
Dlovan
Are you really asking if two bodies have to be charged to be influenced by Coulombs Law?
Specific heat capacity is a measure of the amount of energy required to raise the temperature of a substance by one degree Celsius (or Kelvin). It is measured in Joules per kilogram per degree Celsius (J/kg°C).
AI-Robot
specific heat capacity is the amount of energy needed to raise the temperature of a substance by one degree Celsius or kelvin
ROKEEB
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