Time Frequency Coherence

Hi,

I have just been introduced to time frequency analysis. I am supposed to
do a study on inter-seizure relationships using the concept of
Time-Frequency Coherence. There have been many links of coherence, but not
in the time frequency domain. How do we derive the mathematical
representation of the time frequency coherence of a signal?

If u have ever come across any information for, kindly pls let me know
Thanks alot..


		
This message was sent using the Comp.DSP web interface on
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ryan81 wrote:
> Hi,
> 
> I have just been introduced to time frequency analysis. I am supposed to
> do a study on inter-seizure relationships using the concept of
> Time-Frequency Coherence. There have been many links of coherence, but not
> in the time frequency domain. How do we derive the mathematical
> representation of the time frequency coherence of a signal?
> 
> If u have ever come across any information for, kindly pls let me know
> Thanks alot..

Inter-seizure? Is this in any way medical? Does the coherence you ask 
about have anything to do with an analog of optical coherence length? 
"Pls" = plus? Pals? In Hebrew, there are no vowels. Fortunately, in 
English, we use them.

I'm not sure we use words the same way.

Jerry
-- 
Engineering is the art of making what you want from things you can get.
�����������������������������������������������������������������������

Jerry Avins wrote:

(snip)

> "Pls" = plus? Pals? In Hebrew, there are no vowels. Fortunately, in 
> English, we use them.

It seems that the origin of sine, from the latin sinus,
has origins in adding the wrong vowels to an arabic word.

http://www.pupress.princeton.edu/books/maor/chapter_3.pdf.

-- glen

ryan81 wrote:

> I have just been introduced to time frequency analysis. I'm supposed
> to do a study on inter-seizure relationships using the concept of
> Time-Frequency Coherence. There have been many links of coherence,
> but not  in the time frequency domain.

Poppycock! Try googling for "Time-frequency coherence".

> How do we derive the mathematical
> representation of the time frequency coherence of a signal?

See, for example, the first return from my suggested Google search:

http://208.164.121.55/hbm2003/abstract/abstract956.htm

> If u have ever come across any information for, kindly pls let
> me know

If you ever get around to learning how to use Google, please let us
know.

Ciao,

Peter K.

"glen herrmannsfeldt" <gah@ugcs.caltech.edu> wrote in message
news:vcSdnTi3TtUaXerfRVn-hQ@comcast.com...
> Jerry Avins wrote:
>
> (snip)
>
> > "Pls" = plus? Pals? In Hebrew, there are no vowels. Fortunately, in
> > English, we use them.

The most common internet usage is "please".  But I agree that folks should write
out the whole word.

I think with the growing popularity of phone-based text messaging, often entered
with thumbs on a 10-key numeric keyboard, seeing these abbreviations is going to
become more and more common.  It is certainly understandable to want to
abbreviate when the input methodology is so clumsy and the screens so small.
But that tends to carry over to other systems as well (e.g. Usenet), even though
there is very little need for it.

"ryan81" <alligatorpenguin@hotmail.com> wrote in message
news:KcqdnVFFNIGaN-rfRVn-gQ@giganews.com...
> Hi,
>
> I have just been introduced to time frequency analysis. I am supposed to
> do a study on inter-seizure relationships using the concept of
> Time-Frequency Coherence. There have been many links of coherence, but not
> in the time frequency domain. How do we derive the mathematical
> representation of the time frequency coherence of a signal?
>
> If u have ever come across any information for, kindly pls let me know
> Thanks alot..

I know that there is atleast some work done in this area at the University
of Michigan. Go to their webpages, find Professor William Williams (yes
that's 2 Williams) and check out his research work and references - I'm sure
you'll find something of interest to you. BTW, I'm pretty sure he is the
Willaims in the 'Choi-Williams transform'.

Cheers
Bhaskar

>
>
>
> This message was sent using the Comp.DSP web interface on
> www.DSPRelated.com

glen herrmannsfeldt wrote:
> Jerry Avins wrote:
> 
> (snip)
> 
>> "Pls" = plus? Pals? In Hebrew, there are no vowels. Fortunately, in 
>> English, we use them.
> 
> 
> It seems that the origin of sine, from the latin sinus,
> has origins in adding the wrong vowels to an arabic word.
> 
> http://www.pupress.princeton.edu/books/maor/chapter_3.pdf.
> 
> -- glen

Wow! Notice how my initials are woven into that narrative!

Jerry
-- 
Engineering is the art of making what you want from things you can get.
�����������������������������������������������������������������������

Jerry Avins wrote:

>
> Wow! Notice how my initials are woven into that narrative!
> 

Ja.

Ciao,

Peter K.

On 3 May 2005 17:40:48 -0700, "Peter K." <p.kootsookos@iolfree.ie>
wrote:

>Ja.

"Jah, Rastafahri. Everliving, everfearful, eversure. Sahlisiaieh
da first"   -Bob Marley

very roughly transliterated from the magical original,

Chris Hornbeck

Jon Harris wrote:
> "glen herrmannsfeldt" <gah@ugcs.caltech.edu> wrote in message
> news:vcSdnTi3TtUaXerfRVn-hQ@comcast.com...
> > Jerry Avins wrote:
> >
> > (snip)
> >
> > > "Pls" = plus? Pals? In Hebrew, there are no vowels. Fortunately,
in
> > > English, we use them.
>
> The most common internet usage is "please".  But I agree that folks
should write
> out the whole word.
>
> I think with the growing popularity of phone-based text messaging,
often entered
> with thumbs on a 10-key numeric keyboard, seeing these abbreviations
is going to
> become more and more common.  It is certainly understandable to want
to
> abbreviate when the input methodology is so clumsy and the screens so
small.
> But that tends to carry over to other systems as well (e.g. Usenet),
even though
> there is very little need for it.

Perhaps there is a difference between the US and Europe, but over here,

text messages have been hot for more than five years. I don't know the

traffic statistics for mobile phones, but I wouldn't be surprised if
some
20 - 30% of the traffic between private customers were text messages.
As each text message can only hold 160 characters, lots of "condensed
language" have developed. Some Norwegian teachers (teachers who teach
Norwegian language) are very excited, "this is the most exciting event
in the Norwegian written language since we abandoned the runes and
adopted the latin alphabet!" I don't share their excitement.

Rune (the name apparently stems from old norse and means "he who knows
secrets", hinting at the art of reading and writing being reserved a
select few)