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What is the significance of the number 0.707 or 3dB or 1/sqrt(2)? I see it everywhere, e.g. bandwidth, quality factor, RMS, damping coefficient, and cutoff frequency. Are they all related somehow?
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>>7961326
.707 = cos(45) = sin(45).
-3dB denotes the bandwidth of a signal. That's mostly convention but it is also proportional to [math] \frac{1}{2 \pi \tau} [/math].
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>>7961338
Every constant is proportional to a constant.
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>>7961338
>-3dB denotes the bandwidth of a signal
How so? Last time I checked it denoted an attenuation by the factor of 2^(-1) (or by the factor of 2 if speaking of power).
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so suppose i have a function f(z,t), is it possible to plot it using the plot(or any other) function at say t=3 without declaring t:=3 ?
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bump
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poop
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bump
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How to learn analysis? When it comes to calculations or practical applications I have no problems, but when it comes to proofs I don't even know where to start
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Delete system32.
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sasuga frogposter
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>>7961066
Easy. I'll tell you all about it when I see you again.
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How do humans lock their muscles?
And by that, which I assume is an inaccurate description, how do we hold our arm in a specific position?
What are the electrical signals going to the muscles in the arm like that can hold the muscles there?
I'm in the very early stages of designing a VR extension/utility for a pitch, and this is the first real step in understanding how it would function.
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I would like to know too, just curious
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Within your muscle spindles, there are afferent sensory neurons, Ia/II, which send a signal to your spine when a force is placed on your muscles like filling a cup with water, which creates this downward force. To compensate, without thinking efferent motor neurons leaving your spine determine levels of contraction. Gamma Motor neurons set the gain on your muscles, while alpha motor neurons create excitatory connections with the muscle that you want to contract, while creating inhibitory connections with the opposing muscle, such as the biceps/triceps. On your muscle tendons, Golgi organs like the 1b Neuron limits the amount of contraction to prevent injury.
Was this kind of what you were looking for? I'm happy to answer any questions.
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>>7960773
By the way, this all kind of happens at the inter neuronal junctions within the spine, it sends information to your brain after the signaling pathways have already been activated.
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I was wondering if Nutrition is even a legitimate scientific field? What about dietetics?
All seems like common knowledge to me.
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>>7960744
I'll tell you all about it when I see you again.
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>>7960762
We've come a long way from where we began.
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>>7960770
Oh, I'll tell you all about it when I see you again.
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Hi, anyone of you know how to access and use Sci-Hub, I cant access it, is it down or am I just a complete idiot?
If it is down and you are in a giving mood, I need the paper " Effect of incidence angle on laser scanner intensity and surface data " from osa publishing (applied optics) can be found at: https://www.osapublishing.org/ao/abstract.cfm?uri=ao-47-7-986
Some otter info if needed.
Antero Kukko, Sanna Kaasalainen, and Paula Litkey,
"Effect of incidence angle on laser scanner intensity and surface data,"
Appl. Opt. 47, 986-992 (2008)
Any effort from you will be appreciated, thanks in advanced.
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What country are you in?
In the US go to scihub.org
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>>7960646
filetea dot me/t1sjbH0Uro1SSSHReMmoQ2rDw
Sci-Hub is online whats the problem?
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>>7960666
Im in Norway, when i use the serch function on scihub.org i just en up at a pay wall
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Whilst reading about pain perception in the latest version of Kandel's Principles of Neural Science I got really confused. I understand that morphine acts primarily on mu receptors, and more so than enkephalins or dynorphins. However, on page 552, the book states:
"The number of mu receptors on alpha-gamma nociceptors, which mediate fast and acuate pain or "first pain", exceeds that on C fiber nociceptors, which mediate slow persistent or "second pain". This may help to explain why morphine is more effective in the treatment of persistent rather than acute pains."
Should it not be the other way around if morphine has preference for mu receptors and mu receptors are more prevalent on alpha-gamme nociceptors? Is this a typo in the book?
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>>7960643
It says may. If alpha-gamma nocieptors have more mu receptors that would mean that morphine has a weak signal and isn't processed as efficently in the area with more receptors. The area has low levels of mu and the cells compensate by producing more receptors to increase sensitivity.
C fiber nocieptors have less, which in this context would mean it receives a stronger signal of mu and doesn't need as much receptors.
For more clarification google receptor upregulation and downregulation
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It's a typo. Opiates are much more effective on acute pains.
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Are university's in Asia good?, specifically in Japan, China and South Korea.
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>>7960489
Japan yes, China and Skorea only the top ones are any good, most other degrees out of those countries are worth less than American AS degrees.
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>>7960495
Ok thanks!
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>>7960489
Japanese universities are really easy and most students just skip all their class for 4 years. Their graduate programs are OK.
Chinese universities aren't worth their weight in shit.
Korean universities are meh (many Koreans head off to 'merika ones if they can)
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Is there anything carbon nanotubes CAN'T do?
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>>7960466
cinnamontoastcrunch.meme
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>>7960466
ur mum so fat she the local group centre of mass
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Yeah. I'll tell you all about it when I see you again.
>Hit the public library after uni to do some work almost everyday
>Kid there has a private teacher trying to teach him math
>they always sit behind me so can't avoid hearing their conversations
>a few months ago he was doing fractions
>now he's come to calculus
>feel proud of him for not giving up
We're all gonna make it brahs
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I wish I had a private teacher. Someone teach me math please.
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>>7960459
Next up is category theory!
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>>7960468
Watch khan academy bro, never give up, you're gonna make it.
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What is "stem cell research"?
Is it just some media trope, a legitimate cure for basically anything wrong with a body, or somewhere inbetween?
Pic unrelated, felt like making a Nazi flag with 8901% more funk.
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>>7960263
Currently it's next to useless
It has pretty huge potential though.
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>>7960263
If you made that using some vector editor, like Adobe Illustrator or whatever, could you upload the original vector image somewhere?
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>>7960317
I used Blender.
Anonymous
Weird mark appeared on my back 2016-03-27 06:02:02 Post No.7959857
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Weird mark appeared on my back
Anonymous
2016-03-27 06:02:02
Post No. 7959857
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So the other day I got home from work and was getting ready to hang out. Then my wife points out a weird mark on my back. Before you ask. NO. I didn't sleep on something or get hit by an object. It appeared over night. Other people have had the same problem. Yet the only thing I can find is government alien abduction theories. Any one have any other thoughts?
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>>7959857
virus, selected anus probe candidate, probably slept on something weird.
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alien virus
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>>7959857
the alliums marked you
means ur next sorry
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How could we ever tell we are in a simulation, with out some sci fi cliche giving it away for us?
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>>7959737
By looking at high energy cosmic rays and discovering a discrepancy.
http://arxiv.org/abs/1210.1847
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non-/sci/ here (at least not really, just a software developer), but that topic got me quite curious over the last months, and I've spent a lot of time watching Campbell's lectures and such. In fact, I'm listening to another interview with him right now.
What's the general stance here? Do you guys "believe" this digital universe stuff? Do you take anything from it into your work?
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http://www.smbc-comics.com/?id=2535
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Hi mates, there is a reaction or way to calculate and predict which numbers will fall in income from the lottery?
I'm desperate and life-threatening.
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If there was a way to predict the lottery accurately, then there wouldn't be a lottery.
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>>7959641
It is near impossible.
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>>7959641
Yeah. I'll tell you all about it when I see you again.
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if you get 2 ticks for a win during a winstreak, and a winstreak constitutes having won 3 or more matches in a row, and you get 1 tick for breaking a losing streak which constitutes having lost 3 or more matches in a row, what's the average rate of progress for someone with a 50/50 win rate?
pic unrelated
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>>7959282
*and you get 1 extra tick for breaking a losing streak
and of course, a normal win gives a tick, and a loss loses a tick
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>>7959282
Does the third win in a row count as a "win during a winstreak"?
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>>7959282
America is being destroyed from within at the moment. You get what you'd reserve burgerniggers