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/sci/ - Science & Math

Page 2

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No.10202516 [Reply] [Original] [archived.moe]

Thoughts on these guys?
I'm reading through some of their articles on minor accidents at nuclear power plants, and while most of the actual content appears to be sound and correct, much of the opinion presented or reporting surrounding the content is full of errors, clickbaity writing that reeks of agenda, and stupid analogies that make me question their credibility.
I checked warosu but nobody ever mentions them or said anything of substance

This is just so I can find it in the archive
Union of Concerned Scientists

 >> Anonymous Sun Dec 9 15:33:58 2018 No.10202520 >>10202516>This is just so I can find it in the archiveWhy not put it in the thread title?
 >> Anonymous Sun Dec 9 15:34:45 2018 No.10202522 >>10202520Because I'm a dipshit who was thinking about how much I had to piss while writing that post.
 >> Anonymous Sun Dec 9 15:39:12 2018 No.10202536 Who are they affiliated with or sponsoned by?

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No.10202509   [Reply] [Original] [archived.moe]

(Pls be gentle, I am a brainlet)

I'm struggling with problem 1 here.

I've put it into the modified Bernoulli equation (accounting for head loss from the sharp-edged exit, k=0.5), taking the top of the tank to be z=0 and the bottom z=-h. After rearranging I've gotten to here:

[eqn]z_1(t)=\int_{0}^{t} v(\tau)d\tau=\frac{v(t)^2}{2g}(\frac{3}{2}{}-(\frac{d}{D})^4)-h[/eqn]

Am I on the right track?

1 replies omitted. Click Reply to view.
 >> Anonymous Sun Dec 9 15:32:56 2018 No.10202518 >>10202509Wait, ignore the $z_1(t)$ term, I forgot I divided by the diameter so that's not valid.
 >> Anonymous Sun Dec 9 15:34:03 2018 No.10202521 >>10202509I dont see viscosity in that equation. Also, where does tau come from?
 >> Anonymous Sun Dec 9 15:34:59 2018 No.10202523 >>10202521Dummy time variable for integration from 0 to an arbitrary time t.
 >> Anonymous Sun Dec 9 15:38:48 2018 No.10202533 >>10202523im on my phone cant do algebra to check your work.
 >> Anonymous Sun Dec 9 15:50:57 2018 No.10202568 Wait, should my integral be over z instead of time?

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No.10202489 [Reply] [Original] [archived.moe]

I need help finding the imedence seen by terminals a and B in the following. It is a practice problem from my book and I don’t know how to solve it without eliminating nodes a and b.

10 replies omitted. Click Reply to view.
 >> Tuba Jam !!+Q/vU207C0N Sun Dec 9 17:06:36 2018 No.10202846 >>10202550nah just interested lol
 >> Anonymous Sun Dec 9 17:14:47 2018 No.10202866 File: 2.23 MB, 4032x3024, 6E7CD43F-9A7E-48BB-B794-47F35EA3673B.jpg [View same] [iqdb] [saucenao] [google] [report] This is not turning out well
 >> Anonymous Sun Dec 9 17:16:29 2018 No.10202869 >>10202594is this the same anon that was cooking?
 >> Anonymous Sun Dec 9 17:25:03 2018 No.10202894 >>10202869I'm not the cooking anon
 >> Anonymous Sun Dec 9 17:26:47 2018 No.10202900 >>10202866Not sure what you did thereSolving it on octave gives me Z = 4.69 - 0.98j

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No.10202473 [Reply] [Original] [archived.moe]

How much of a meme is data science? Does a BS in math from a state university with a 3.0 GPA have any hope of landing a job as a data scientist? Not exactly a brainlet but I struggle to work on anything more than 40 hrs a week.

7 replies omitted. Click Reply to view.
 >> Anonymous Sun Dec 9 16:24:30 2018 No.10202695 >>10202500that sounds like an SQL job for a company
 >> Anonymous Sun Dec 9 16:27:03 2018 No.10202704 >>10202500Sounds dull
 >> Anonymous Sun Dec 9 18:10:19 2018 No.10203028 >>10202636That makes sense, but how are outcomes for the business causally tied to your intervention using data?
 >> Anonymous Sun Dec 9 18:13:10 2018 No.10203040 >>10203028They aren't, which is why there are no job openings
 >> Anonymous Sun Dec 9 18:19:09 2018 No.10203063 >>10203028Anon, if you were too low iq to know that iq existed, how would you know to increase it?

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No.10202463 [Reply] [Original] [archived.moe]

how hard would it be to replicate alphazero at home based on the publically available descriptions of its mechanism? any big unknown remainders left that would be too hard to reverse-engineer?

 >> Anonymous Sun Dec 9 15:06:44 2018 No.10202468 >how hard would it be to replicate alphazero at home based on the publically available descriptions of its mechanism?Why don't you try it and find out?
 >> Anonymous Sun Dec 9 15:10:49 2018 No.10202475 >>10202468i would assume there's some proprietary original research involved which would be impossible to calculate for a non-expert. so i'm asking /sci/

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No.10202461 [Reply] [Original] [archived.moe]

Has math changed a lot over the course of nearly 150 years?

https://www.youtube.com/watch?v=KzJjlg3wvew

4 replies omitted. Click Reply to view.
 >> Anonymous Sun Dec 9 15:16:50 2018 No.10202486 >>10202461She is so perfect
 >> Anonymous Sun Dec 9 15:19:01 2018 No.10202488 >>10202486How? Her face is so ugly
 >> Tuba Jam !!+Q/vU207C0N Sun Dec 9 15:59:42 2018 No.10202591 >>10202467RIP geometric intuition as part of the standard pedagogypress f to pay respects
 >> Anonymous Sun Dec 9 16:04:14 2018 No.10202606 >>10202461I don't know about 150 years, but I have an engineering textbook from the 20s covering multivariable calc, ODEs, PDEs, and statistics, and everything is exactly the same as we learn today, except they discuss numerical approximation methods that are obsolete due to computers.
 >> Anonymous Sun Dec 9 16:50:42 2018 No.10202797 >>10202480No, the derivative of a function used to be calculated geometrically. See: https://www.youtube.com/watch?v=ObPg3ki9GOI&t=115s (1:55)>>10202591F

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No.10202434 [Reply] [Original] [archived.moe]

>feyerabend
thoughts?

 >> Anonymous Sun Dec 9 14:56:23 2018 No.10202441 >>10202434What is it?
 >> Anonymous Sun Dec 9 14:58:02 2018 No.10202444 >>10202441who? feyerabend was a philosopher of science
 >> Anonymous Sun Dec 9 15:00:19 2018 No.10202448 >>10202444Not the text, the snake in the thumbnail.

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No.10202424 [Reply] [Original] [archived.moe]

Why couldn't we just fill the atmosphere with an aerosol substance and force the world to cool like that, in order to end Global Warming?
If anything, we could just plunge the world into another ice age.

 >> Anonymous Sun Dec 9 14:57:49 2018 No.10202443 NIMBYism
 >> Anonymous Sun Dec 9 14:59:41 2018 No.10202447 >Another ice age would be better than temperatures a few degrees warmerPeople on the left shouldn't be allowed to get involved in science, your retarded emotions cloud your judgement and you're ruining everythingLibertarian scientists rise up
 >> Anonymous Sun Dec 9 15:00:32 2018 No.10202451 >>102024242nd law of thermodynamics says that in cleaning up one mess, you are actually making a bigger mess somewhere else. Anyone who tries to sell you things that seem to be too good to be true is a crook.
 >> Anonymous Sun Dec 9 15:37:39 2018 No.10202527 >>10202424I know. We could use aluminum oxide while claiming it's to reflect out the sun, but we're really just beaming it with phased array radar to heat it up and control the weather.I know, we could just deploy calcium carbonate in the air and claim it's safe. But when it reacts with UV, it's the ideal environment for us to do other stuff...

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No.10202407 [Reply] [Original] [archived.moe]

When do you think shit will hit the fan globally in terms of climate change? Like a great worldwide economic depression because of climate disasters.

8 replies omitted. Click Reply to view.
 >> Anonymous Sun Dec 9 17:25:01 2018 No.10202893 Government will take care of itI just need to vote for the credible man to president and congress
 >> Anonymous Sun Dec 9 17:26:10 2018 No.10202896 >>10202882>alarmists>not scientistsBefore we had very little understanding of the impacts, and people like Al gore ended up soiling the name climate scientist. Obviously we're going to get it wrong since scientists cant predict human carbon emissions exactly and this has never happened before. The idea that people in the 80 would know what would happen in the 2010s is like giving a final for a class on the first day.
 >> Anonymous Sun Dec 9 18:15:16 2018 No.10203048 >>10202407>When do you think shit will hit the fan globally in terms of climate change? Like a great worldwide economic depression because of climate disasters.5 years ago according to Al Gore
 >> Anonymous Sun Dec 9 18:17:47 2018 No.10203056 >>10203048Are you retarded?
 >> Anonymous Sun Dec 9 18:19:41 2018 No.10203065 >>102030489 years ago according to the UN

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No.10202399 [Reply] [Original] [archived.moe]

One can increase the size of crystals produced in a semi-batch reaction by:
1- decreasing reactant concentrations
2- increasing feeding time(i.e lowering feed-rate)
3-increasing agitation rate
4-increasing mixing intensity at the feed point.

But what might be some drawbacks to making these changes? Thanks if you can help!!

 >> Anonymous Sun Dec 9 14:49:35 2018 No.10202414 There aren't any. Dial all 4 parameters to the end, you get the best crystals ever.
 >> Anonymous Sun Dec 9 14:53:18 2018 No.10202427 >>10202414some of them might actually not have drawbacks, but I at least know with #3 increasing the agitation rate beyond a certain point will begin to reduce the crystal size u goof
 >> Anonymous Sun Dec 9 14:54:36 2018 No.10202436 >>10202399hi intro to chem-E idiot.1. higher flow rate to get same mass yield -> higher capital cost and energy for heating and pumping. higher volume is also a safety risk.2. similar to 1. need to parallelize to get same mass rate. 3. agitation is energy intensive and hard to scale up. further, agitation competes w/ crystal size because they will break up. 4. see 3.t. your TA.
 >> Anonymous Sun Dec 9 15:00:34 2018 No.10202453 >>10202436thank you very much big guy

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No.10202383 [Reply] [Original] [archived.moe]

I bet I'm a dumbass for not knowing this, but how do you solve this?

23 replies omitted. Click Reply to view.
 >> Anonymous Sun Dec 9 17:24:58 2018 No.10202892 File: 255 KB, 668x3541, solution.png [View same] [iqdb] [saucenao] [google] [report]
 >> Anonymous Sun Dec 9 17:27:15 2018 No.10202901 >>10202892>got that premium
 >> Anonymous Sun Dec 9 17:33:17 2018 No.10202925 >>10202892that is fucking stupid and whoever assigned this to OP or put this in their textbook needs to be gassed
 >> Anonymous Sun Dec 9 17:35:40 2018 No.10202934 >>10202892Math is beautiful
 >> Anonymous Sun Dec 9 17:40:59 2018 No.10202950 >>10202925Half of these steps can be made in your head.

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No.10202359 [Reply] [Original] [archived.moe]

So what is accountable for higher intelligence in people? Nurture aside, there must be a physiological component. What would need to be enhanced for a person to become smarter, if it was possible to do it?

 >> Anonymous Sun Dec 9 14:33:17 2018 No.10202370 The key to making people smarter is to increase their intelligence
 >> Anonymous Sun Dec 9 14:35:01 2018 No.10202373 >pepe>>>/tv/
 >> OP Sun Dec 9 17:08:24 2018 No.10202848 bump

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No.10202293 [Reply] [Original] [archived.moe]

>CS is just a meme

Pic related was my final I just turned in, I doubt anyone not in CS could even do it.

29 replies omitted. Click Reply to view.
 >> Anonymous Sun Dec 9 17:39:00 2018 No.10202946 >>10202920>its been solved by brute force>eludes researchersits almost like they arent just looking for an algorithm that will eventually halt, but are instead looking for a more efficient solution. Since brute force takes a really long fucking timefrom the website"The simplicity of the statement of the problem is deceptive -- the TSP is one of the most intensely studied problems in computational mathematics and yet no effective solution method is known for the general case. ">Secondly, as I already said, the OP post adds more restrictionsBut OP's post also lets you have more than one path from city A to city B, so it also takes away the restriction of having only one path for each pair of locations.
 >> Anonymous Sun Dec 9 17:47:37 2018 No.10202966 >>10202293first of all, let's eliminate the unecessary facts>drivers leave at 8am>18mph>40 packages a dayall irrelevant because the shortest distance is asked, not the shortest time period. yes that also implies that the trucks don't have to be done by the end of the day, since there are no constraints placed on that>a truck can hold 16 packages irrelevant since multiple trucks decrease time, but not distance since they all start at the same pointthis literally leaves us with:>find an algorithm for a truck to deliver 16 packages with a minimal distancewhich makes it a tsp with n=16 which makes it a retarded and boring problem
 >> Anonymous Sun Dec 9 18:12:49 2018 No.10203038 >>10202920For n > 10, the problem takes an absurd amount of time. An $O(n!)$ solution is intractable your computer and certainly mine. Nobody cares about the trivial cases for something around 5-6 cities.>Hurr durr, a general bound of $(O,(n^4), O(n^3 \cdot 2^n))$ is solved
 >> Anonymous Sun Dec 9 18:14:04 2018 No.10203043 >>10203038*$(O(n^4), O(n^3 \cdot 2^n))$
 >> Anonymous Sun Dec 9 18:16:33 2018 No.10203052   >>10202966>but muh [math]\textsc{NP-HARD}[/math}

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No.10202286 [Reply] [Original] [archived.moe]

Almost everybody here has seen this before, but I'm wondering, what happens if we time reverse it? Does b moving up pull spacetime through the other end of the portal?

 >> Anonymous Sun Dec 9 14:10:35 2018 No.10202305 What if instead of reversing time, you make time go sideways?
 >> Anonymous Sun Dec 9 14:11:43 2018 No.10202310 How about if you turn time in a boat halfway through? What would happen?
 >> Anonymous Sun Dec 9 14:15:11 2018 No.10202320 File: 234 KB, 768x1024, 1536624400539.jpg [View same] [iqdb] [saucenao] [google] [report] >>10202286The "time forward" situation is nonphysical to begin with. It is complete nonsense to even ponder it.
 >> Anonymous Sun Dec 9 15:38:14 2018 No.10202531 File: 46 KB, 1000x2000, For A fags.png [View same] [iqdb] [saucenao] [google] [report]
 >> Anonymous Sun Dec 9 15:49:05 2018 No.10202561 >>10202286Velocity is relative, so saying the space on the other side of the portal is moving relative to the cube is obviously equivalent of saying the cube is moving relative to the space, indicating scenario B.

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No.10202282 [Reply] [Original] [archived.moe]

I'm going to take acid in 4 days(not my first time), whats the best way to prime my mind with information so I can have a "mind altering trip"?

I'm thinking about reading selected texts all day every day so I'm forced to make connections between the texts and other ideas in my mind

Does priming only work on the daily scale or should I push the date out a couple weeks so I can prime by reading all day for an extra number of weeks?

6 replies omitted. Click Reply to view.
 >> Anonymous Sun Dec 9 14:24:14 2018 No.10202343 >>10202333just to know if anybody has any knowledge about the priming affect, but I guess i'll do some research on the subject
 >> Anonymous Sun Dec 9 14:26:00 2018 No.10202346 >>10202282Smoke weed every day.Call over some hookers
 >> Anonymous Sun Dec 9 14:27:25 2018 No.10202350 Suggested media:The Metamorphosis, Winnie the Pooh and the blustery day, Peter Zeihan's newsletter.
 >> Anonymous Sun Dec 9 14:55:25 2018 No.10202439 >>10202333>guy who discovered DNAI assume you're talking about Kary Mullis and he discovered PCR, not DNA
 >> Anonymous Sun Dec 9 15:05:53 2018 No.10202464 >>10202311Nah 100 is perfect. 200 is where the real shit begins. Not safe territory.

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No.10202281 [Reply] [Original] [archived.moe]

I know anonymity makes a person feel free to do whatever shit he wants
>> but it generally tends to go towards more offensive/ aggressive side
>> people do stuff that they won't really do irl unless they're anonymous.
>>So what do they tell you psycho chads what do your studies say.
>> I want to know is that the real human nature to do fucked up shit or is it something that anonymity induces.

 >> Anonymous Sun Dec 9 16:19:47 2018 No.10202674 It is simply truth. The few flowers that bloom in the wasteland gives hope.

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No.10202270 [Reply] [Original] [archived.moe]

I'm an absolute disaster in Combinatorics. What books and resources are there that cover from the basics (Arrangements, permutations and combinations) to more advanced stuff? I'm relatively O.K. in Calculus and Trig.

4 replies omitted. Click Reply to view.
 >> Anonymous Sun Dec 9 14:23:31 2018 No.10202342 >>10202331Because I suck at it, and it sucks ass.
 >> Anonymous Sun Dec 9 16:32:08 2018 No.10202725
 >> Anonymous Sun Dec 9 18:09:27 2018 No.10203027
 >> Anonymous Sun Dec 9 18:16:17 2018 No.10203050 >>10202270>What books and resources are there that cover from the basics (Arrangements, permutations and combinations) to more advanced stuff?Stanley - Enumerative Combinatorics vol 1 and 2
 >> Anonymous Sun Dec 9 18:20:19 2018 No.10203068 >>10202270Lovasz.

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No.10202267 [Reply] [Original] [archived.moe]

Anons,
I want to teach you how you can create
a language without using a base language.

Pay close attention to these few pictures,
this is all you need to know for now.

1 - an observation
2 - movement of the observer

What it is when an observer translates
an observation into movement.

1 replies omitted. Click Reply to view.
 >> Anonymous Sun Dec 9 13:58:01 2018 No.10202278 what use is your language between two people who mutually disagree about the nature of every possible observation
 >> Anonymous Sun Dec 9 14:02:02 2018 No.10202285 File: 139 KB, 661x704, M2.jpg [View same] [iqdb] [saucenao] [google] [report] Likely as far as you understand, a language, mathematics, musical notations, any models..are specific sets of observations that lead to a specific set of movements - crucial information when translating languages to another. I will try to simplify this even further and then come up with the best teaching methods, hopefully this helped some of you at least.
 >> Anonymous Sun Dec 9 15:07:41 2018 No.10202470 >>10202278I'm not even joking with this one, but when go further into this topic, "the observation" can be an interaction to the observer you describe as punches,and these punches and pain make the observer do the things you desire.Everyone understands pain. The actions you do after being hurt by "an observation", like a hot stove for example, this fundamentally goes into the same category as words you are reading at this very moment, nice, right?
 >> Anonymous Sun Dec 9 15:10:16 2018 No.10202474 >>10202470Contrary to your unfounded assertion, not everybody understands pain.
 >> Anonymous Sun Dec 9 15:11:12 2018 No.10202477 D-did you just invent Swedish..??

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No.10202263 [Reply] [Original] [archived.moe]

Quantum physicists never understood the double-slit experiment from a classical perspective.

I simulated the double slit setup and got an interference pattern with the particles just being hard balls that bounce off walls elastically. One ball at a time worked fine.

I tooled around with the parameter and found only if you take them too the extreme does the pattern disappear.

I've summarized the two approaches to the double-slit experiment in pic related.

85 replies omitted. Click Reply to view.
 >> Anonymous Sun Dec 9 18:12:28 2018 No.10203036 File: 10 KB, 400x400, spread answers.png [View same] [iqdb] [saucenao] [google] [report] >>10203025ok heres a racist cartoon which is also the solution
 >> Anonymous Sun Dec 9 18:14:00 2018 No.10203042 >>10202263>This triggers the pop/sci/
 >> Anonymous Sun Dec 9 18:18:42 2018 No.10203060 >>10203015No, I said that of the particles that get through, the fraction that reflect at all goes roughly as slit thickness divided by source distance. You just never responded to that point because it proves you wrong.
 >> Anonymous Sun Dec 9 18:23:28 2018 No.10203078 >>10203010They aren't here at pictures with P1 or P2. It's probably from the other slit being covered only partially by the mask so there is still some interference as the mask isn't at point blank from distance from the slits.
 >> Anonymous Sun Dec 9 18:27:03 2018 No.10203086 Nice troll OP, but seriously you haven't disproved jack shit.First of all, the double slit experiment has always been presented as a thought experiment to illustrate how weird QM is and "wave-like" properties of matter, but having a classical alternative explanation (which you don't have) doesn't explain jack shit about all the other experimental evidence for QM. How on earth do you explain the stern-gerlach experiment, photoelectric effect, the selection rules of hydrogen, Bragg's law, radiation, the whole standard model etc. If you have an alternative explanation for a single Quantum mechanical effect, that doesn't gives you a full working model like QM.Secondly, obviously you can get that sort of distribution by collision you absolute brainlet, why people are asking you to plug in the actual parameters from an experiment and compare you result is to see if IT FITS EXPERIMENTAL DATA. If you have something that looks like an interference pattern, well that's great, but you need to compare it to the experimental data gathered from the articles already presented to you. Obviously a distribution of initial angles will give you at the end a distribution of final trajectories, this is what classical scattering is all about, but the point here is in that in these experiments they collimate the beam to avoid that noise, and actually get a direct comparison with theoretical models.

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No.10202251 [Reply] [Original] [archived.moe]

I'm currently in my second year of uni and I want to study math but when I was in highschool I didn't take any calculus, which has effectively delayed my maths education by at least a year. I've gotten an A in every math course I've taken at uni and expect to get an A in multivariable, linear algebra, and proofs this semester, but I can't shake the feeling that I'm a brainlet for not starting my "real" math courses until the spring semester of my second year. How far behind am I compared to the average math major at a mid tier uni?

pic unrelated

 >> Anonymous Sun Dec 9 13:47:47 2018 No.10202254 from the sounds of it, about 1-2 years. no biggie

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