# 0.1 Lab 1 - discrete and continuous-time signals  (Page 4/5)

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## Processing of speech signals

Digital signal processing is widely used in speech processing for applications ranging from speech compression and transmission,to speech recognition and speaker identification. This exercise will introduce the process of reading and manipulatinga speech signal.

First download the speech audio file speech.au , and then do the following:

1. Use the auread command to load the file speech.au into Matlab.
2. Plot the signal on the screen as if it were a continuous-time signal (i.e. use the plot command).
3. Play the signal via the digital-to-analog converter in your workstation with the Matlab sound function.
Submit your plot of the speech signal.

## Attributes of continuous-time signals

In this section you will practice writing .m-files to calculate the basic attributes of continuous-time signals.Download the function signal1.p . This is a pre-parsed pseudo-code file (P-file), which isa “pre-compiled” form of the Matlab function signal1.m . To evaluate this function,simply type y = signal1(t) where t is a vector containing values of time.Note that this Matlab function is valid for any real-valued time, t , so y = signal1(t) yields samples of a continuous-time function.

First plot the function using the plot command. Experiment with different values for the sampling periodand the starting and ending times, and choose values that yield an accurate representation of the signal.Be sure to show the corresponding times in your plot using a command similar to plot(t,y) .

Next write individual Matlab functions to compute the minimum, maximum, and approximate energy of this particular signal.Each of these functions should just accept an input vector of times, t , and should call signal1(t) within the body of the function. You may use the built-in Matlab functions min and max . Again, you will need to experiment with the sampling period,and the starting and ending times so that your computations of the min, max, and energy are accurate.

Remember the definition of the energy is

$\text{energy}={\int }_{-\infty }^{\infty }{\left|\text{signal1},\left(,t,\right)\right|}^{2}dt\phantom{\rule{4pt}{0ex}}.$
Submit a plot of the function, and the computed values of the min, max, and energy.Explain your choice of the sampling period, and the starting and ending times.Also, submit the code for your energy function.

## Special functions

Plot the following two continuous-time functions over the specified intervals. Write separate script files if you prefer.Use the subplot command to put both plots in a single figure, and be sure to label the time axes.

• $\text{sinc}\left(t\right)$ for $t$ in $\left[-10\pi ,10\pi \right]$
• $\text{rect}\left(t\right)$ for $t$ in $\left[-2,2\right]$
The function rect(t) may be computed in Matlab by using a Boolean expression.For example, if t=-10:0.1:10 , then $y=rect\text{(}t\text{)}$ may be computed using the Matlab command y=(abs(t)<=0.5) .

Write an .m-script file to stem the following discrete-time function for $a=0.8$ , $a=1.0$ and $a=1.5$ . Use the subplot command to put all three plots in a single figure.Issue the command orient('tall') just prior to printing to prevent crowding of the subplots.

where we get a research paper on Nano chemistry....?
what are the products of Nano chemistry?
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
learn
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
learn
da
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Bhagvanji
Preparation and Applications of Nanomaterial for Drug Delivery
revolt
da
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
I only see partial conversation and what's the question here!
what about nanotechnology for water purification
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
Nasa has use it in the 60's, copper as water purification in the moon travel.
Alexandre
nanocopper obvius
Alexandre
what is the stm
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
Hafiz
what is Nano technology ?
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
why we need to study biomolecules, molecular biology in nanotechnology?
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
why?
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
how did you get the value of 2000N.What calculations are needed to arrive at it
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