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
I'm interested in biological psychology and cognitive psychology
Communication is effective because it allows individuals to share ideas, thoughts, and information with others.
effective communication can lead to improved outcomes in various settings, including personal relationships, business environments, and educational settings. By communicating effectively, individuals can negotiate effectively, solve problems collaboratively, and work towards common goals.
it starts up serve and return practice/assessments.it helps find voice talking therapy also assessments through relaxed conversation.
miss
Every time someone flushes a toilet in the apartment building, the person begins to jumb back automatically after hearing the flush, before the water temperature changes. Identify the types of learning, if it is classical conditioning identify the NS, UCS, CS and CR. If it is operant conditioning, identify the type of consequence positive reinforcement, negative reinforcement or punishment
nature is an hereditary factor while nurture is an environmental factor which constitute an individual personality. so if an individual's parent has a deviant behavior and was also brought up in an deviant environment, observation of the behavior and the inborn trait we make the individual deviant.
Samuel
I am taking this course because I am hoping that I could somehow learn more about my chosen field of interest and due to the fact that being a PsyD really ignites my passion as an individual the more I hope to learn about developing and literally explore the complexity of my critical thinking skills