Math / Science

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Determine the roots in the following case :
 i. Square roots of i
ii. Square roots of (1+i)
iii. Square roots of 1+sqrt(3) i

Total no hints on how to solve the problem. ANy idea ?
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Angular Fundamentals
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Angular Fundamentals

Learn the fundamentals of Angular 2, a JavaScript framework for developing dynamic single page applications.

I need to use compression to change bit depth of a video signal.  

Our Focal Plane Array(FPA) is Vanadium Oxide(VOx) Resistive Microbolometers Uncooled Thermal Infrared Detector.  The output of this image sensor is 14-bit, Wide Dynamic Range(WDR), raw, monochrome, 640 x 480 resolution.  The pixels of this video signal will be processed by Image Signal Processor(ISP).  ISP input is 12-bits.  Therefore, I need to compress FPA output to 12 bits and then input into ISP.

How to perform global tone mapping using two methods, PWL and LUT (curve defined by lut) based mapping.  I need to tone map 14 bit data to 12 bit.  What does PWL stand for?  Please provide sufficient information so I can achieve this.  It's suppose to be similar to gamma compression.  I can do gamma correction in matlab.  Can this tone mapping also be done in matlab?  If yes, please provide some examples.
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Please explain Gamma Compression algorithms. How to write Gamma Compression algorithms for typical video and image processing system?  Please provide some detailed examples.  How to gain sufficient understanding to be able to write Gamma Compression in 'C' or MATLAB?
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I was asked last night about performing maths with quadratic equations and I could show how to solve most problems but there was one that has left me completely baffled.  After about 45 minutes last night I had to give up.  (Probably missed something obvious and was making life way to complex for myself.)

Given the following quadratic equation:
4x.x - 35x + q = 0
what is the value of q.  One is also told the raltionship between two values of x which solve the equation.  Call those solution n and m then n = m squared (n = m.m).

I can use formulae from vieta to obtain things like m + n = 35/4 and m.n = q/4 and the formula for solving the quadratic but I then just get a horrendous mess with quadratic or higher equations when trying to simplify things.

Can someone point me in the right direction please.
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There are 39 numbered ping pong balls. The people who control the handling of the balls have a very complex way of making the draws 100% random.
The cash rewards are for 2-3-4 or 5 numbers.

The chances of one of our 5 numbers drawn in the first draw is 5 in 39 or 12.82% = ?
Then the chances of one of our other 4 numbers being drawn in round two would be 4/38 = 10.52% = ?

Their site says the chances for match 2 is 9.2%
3 = 1 in 95
4 = 1 in 3042
5 = 1 in 501.942

If four of our numbers have been drawn there are only 35 numbers left to be drawn. Why isn't the chance on the 5th number 1/35?
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How do I go about this?

5 liters but they come in 4 packages --> $11.95 - $2.49 to give me 4 packages out of 5 .. not sure if I'm on the right track


m1.png
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I'm going a few more of these questions (Good news is that I might be close to an offer.... light at the end of the tunnel to get away from my moody, abusive manager)

A pump needs 18h to fill a swimming pool. If we add one additional pump that has a 50% larger flow than the first one, how much time will both pumps working together need to fill the same swimming pool?

A pump = 18 hours
B pump = 9 hours (this is my assumption because this pump is 50% larger so it should take half of the amount time of A)

(18 * 9) / 18 + 9 = 6 hours = 3600 mins but this isn't correct.
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I've bought a sample test to practice my upcoming interviews.

I don't know how to go about this one. Any help would be great.

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I don't know where to pu this question so I'm putting it under C# and .Net.

I have another interview on Friday and I was told there will be numerical logic whatever testing on a whiteboard. Ugh. I'm seriously thinking about saying I won't do it but of course I can't. Not that interested in the position so I might end up saying it. Why so some companies put the candidate thru the grinder?!

Anyway, I'm practcing some questions. Is the answer to this question 12?

How old is Jane ... if in 38 yrs... she will be 3 times as old as she is today?
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Rowby Goren Makes an Impact on Screen and Online
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Rowby Goren Makes an Impact on Screen and Online

Learn about longtime user Rowby Goren and his great contributions to the site. We explore his method for posing questions that are likely to yield a solution, and take a look at how his career transformed from a Hollywood writer to a website entrepreneur.

What are some common conversational terms used when discussing the BigO notation?

I think this wold be a good way to give me more exposure to learn the meaning of common terms used when discussing the BigO notation.

Please provide as many as come to mind...

Thanks
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What performance consideration (for sorting) are there in .NET regarding various List Types? Arrays? Other?

What options are there when choosing a list type to use to hold large amounts of data? And what are the advantages of one of the other in a quick sort-time is required?

And, besides sorting, where would performance be a consideration?

Thanks
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How are elements grouped in the periodic table?
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The big terms of BigO Notation

I want to drill down into BigO, but hope to do so from a usefulness perspective. So, regarding making low-level algorithms more performant, for example. Or, from a memory management view...

Suggested topics to read up on? And a site where I can read this?

Thanks
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The diagonal length of the square from corner to corner is 19 inches.  Formula for the 4 equal sides of the square.
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Hi there.

I have trouble how to do this in STATA: I have a dataset with response (BOR) for the patients. The variable BOR can be CR, PR, SD, PD or NE. Each patient can be in either arm A or B. I need to make a table in STATA with the distribution of BOR on arm A and B, and I also need to calculate a p-value (log-rank) and Hazard ratio for each value of BOR.
Anyone who can tell me how to do this in STATA? If not STATA, when maybe the codes in an altertative statistics software? It's probably very much alike.
Thank you in advance.

Best regards

Ulrich
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Why does a football fly better with a good spiral?
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Hello and Good Evening Everyone,

             After reading this rather scientific intriguing article at  https://returntonow.net/2019/01/16/extinct-tree-brought-back-to-life-from-2000-year-old-seeds-archaeologists-found-in-a-clay-jar/?fbclid=IwAR07q4dEZr8c065jVS1Zr6NW6QDkVF70OSPHE6y05jrPQFVknt4dUIznksQ , I have the following question:  Is it possible to bring back to life an extinct species of tree by simply planting a seed of this extinct tree?   It seems to me that the seed would be dead and can not be expected to bring to life any species of tree or living plant.  But, could the seed itself be treated somehow scientifically and then planted in order to bring to life this extinct tree as indicated within the article?  Unfortunately, my scientific knowledge is merely limited to the general courses required to obtain my college degree in addition to never having a botany course per se.

              Any shared thoughts regarding this question will be appreciated.

              Thank you

              George
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How many triangles are there

pic
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Introduction to R
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Introduction to R

R is considered the predominant language for data scientist and statisticians. Learn how to use R for your own data science projects.

Can anyone figure out my grandson's Year 4 Math homework? (He is 8!)

I've attached a photo of it.

The Easy and Speedy part is fine.

However "Some subtracting" is weird - those middle numbers crossed out are on the original sheet. I can't figure out how they work. The subtractions themselves obviously work if you just ignore the crossed out numbers, and adjust for hundreds, tens and units, but why are the crossed out numbers there in the first place? They must be some sort of working out, but what? I come up with a rule that explains some of them but I can't explain them all.

Then finally there is 12, 13 and 14: "Choose three numbers to create a 3-digit number. Re-arrange the digits and subtract the smaller number from the larger number. Do this three times". This doesn't seem to me very clear. Is this what they are looking for:

Choose three numbers: 1 8 6
Re-arrange the digits and subtract the smaller number from the larger number: 8 - 6 - 1 = 1

Do this three times - just choose three numbers another two times?
Choose three numbers: 3 9 2
rearrange and subtract: 9 - 3 - 2 = 4

Choose three numbers: 3 8 2
rearrange and subtract: 8 - 3 - 2 = 3

But since these follow from 9, 10 and 11 perhaps the three numbers are similar to those? But I don't see how?

Anyway here are the original questions:
IMG-20190123-WA0000.jpg
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I'd like to use Photoshop to be able to construct Floor Plans for home building.

In my initial research I noticed the Measurement Scale option that is an inches to pixels conversion. This seems to work well, but isn't quite accomplishing what I want:

I'd like to set this up for Inches to Feet, such that 1/4" is equal to 1' for the sake of accuracy. So, a quarter-inch on the screen (presumably Greyscale at 300dpi) is equal to a foot in real life.

I appreciate your assistance as it turns out that yes, I do indeed need to do math for this.

Thanks!
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Hi,
I want to know how does the body processes oils that we eat.
Does the oil gets stored in the body ?
Or does it get expelled.
Is there any good video explaining it ?
And good site or anything which shows the link between food and its processing and how good food effects the body and how bad food destroys it.
What makes junk food bad why does it cause diseases etc etc ?

Thanks
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STEM education is growing rapidly and preparing the next generation to fulfill the needs of our society's technology demands.  

In what ways has EE helped you continually learn, even as professionals?
How can EE support STEM as a great learning resource?
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I have an image which is 320x240 px

I have an array of values for each pixel in the image (76,800 points)

If the user hovers over any part of the image I need to look at the array and return the corresponding value for it.

i.e.
X Y position [0,0] of the image = the first value in the array.

If I wanted to find out the X Y position [65,33] of the image, and then look up the  value in the array, what would be the correct forumla to do this
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Well I was revising how 'magnetic' force is created and I came up to an issue?

Why do we measure only the charge net density only from a frame reference that electrons dont move?
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