Math / Science

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Is there a tool to calculate line checksum of motorola S3 Record ?

For example, following is line of motorola S3 Record:


To calculate checksum manually, one byte of size, four bytes of address, and all data bytes are summed.  Extract least significant byte
from the sum, take it's one's complement and that's the checksum.

Is there a checksum calculator or tool that will calculate the checksum ?
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Imagine you have a dataset of rowers. You have X variables such as weight, benchpress, deadlift, squat, nutrition, etc. You also have each rower's lap time.

Now, let's say for a given rower, you want to optimize her lap time, but you can only train along ONE DIMENSION. How would you identify the best attribute to optimize?

I thought about a grid search, but that seems awful. Which family of machine learning algorithms would be best for this type of problem, and how would you attack it?

Thanks a million!
Hello Experts!

Please bear with me, as I start from the beginning...

The Setup:

(Real details have been removed)

Our customers have the ability to print their artwork/logo on 10x10 sheets of paper. Through the years, we have converted many printed jobs.  So I have a dataset that includes:

  • Product Dimensions
  • Artwork Dimensions

With knowing that information, I can calculate the '% of Ink Coverage' for each printed job.

So for example,... "Our customer printed a 5x5 logo, on a 10x10 sheet of paper. Thier % of Ink Coverage is 50%".

The Problem

The overwhelming majority of our customers, do not know artwork dimensions at the time of quoting. As you can imagine, determining a price can be very difficult.

As of today, in order to still offer a quote to our customer - we quote them: 10x10 sheet of paper with a 2x2 artwork dimension.

The major flaw with this approach,... is the 2x2 artwork dimension we are quoting - really is just a guess. (Maybe not a complete stab in the dark but I know we did not take a close look at historical data to determine this 'temporary' artwork value)

The Goal

While it's near impossible to guess the exact printed dimension our customer will ultimately use, it's our goal to suggest dimensions that will be close to or OVER what the customer will most likely choose at the time of order.

(Before final artwork was received)
10x10 …
available lengths of four sides  are AB 06 meter,BC 14 meter  CD  01  meter and DA  15 meter ,
whats the area of this plot ,in a calculation i got 0.3027040  cent . is it  correct ?
I am trying to rotate an object and get the following error message: 1119:access of possibly undefined property Math through a reference with a static type class. Thank you for your help

 here is the code


stage.addEventListener(MouseEvent.MOUSE_MOVE, FollowMouse);
function FollowMouse(event:MouseEvent):void
      var SideY:Number = mouseY-circle.Y;
      var SideX:Number = mouseY-circle.X;
      var Rad:Number = Math.atan2(SideY,SideX);
      var Deg:Number = Rad * 180/Math.PI;
      circle.rotation = Deg;
I'm trying to create illegal instruction reset.  

I'm programming Infineon TC29x Aurix Tricore Microcontroller based embedded system in 'C' language.  

I need to set program counter to illegal address, i.e. 0x00FF FFFC.  Can this be done with assembly language instructions?
If yes, please instrument assembly language instruction that would set program counter to 0x00FF FFFC while code is running.
I have a client who has an issue getting the LINEST() function to work for them.  This is my first time using LINEST(), and what seemed, at first, to be straightforward has deepened considerably in levels of complexity.  I am an accomplished VBA programmer, and I feel the best way to give the client what they need is to duplicate the equation in VBA to calculate the slope (m) when there are multiple X Axes.  When only one X axis exists, I have validated LINEST against my own independent calculation, as shown by the equation below.

slope (m) calculation for single X Axis
I am looking for a similar equation I can apply, given 2 or more X Axes.  Reproducing the underlying query in VBA will make for a much more versatile function, capable of calculating LINEST in a more wide-ranging set of circumstances than Excel currently allows, thus meeting my client's requirements.  For those not familiar with LINEST(), I have included a couple of sites that have given me the best start on solving the problem.  The office support site provided the equation, as shown above, which gave me a reliable means to have an independent check against the Excel function on a single X axis.  Every site I've seen thus far provides the LINEST() equation for multiple X Axes, but nowhere have I seen a more nuanced formula that tells me what Excel is doing to derive that number.  That's my missing piece.

Thanks, in advance, for your support.  ~ Peter Ferber
Attached is data dump of some example symbol "ast".  This symbol starts at address 0x0000 6814.

What is oriented display and what is line break at 2 power x ?
The following problem refers to strings in A, B, ..., Z.

How many four-letter strings are there that begin with O ?
I heard gastritis and heartburn can be solved by ingesting alkaline substances.
Alkaline plants supposedly containing alkaline substances can be ingested to lower the pH value in the stomach due to stomach acid.
I'm trying to extract alkaline substances from plants using simple boiling extraction.
Thus, I tried to extract alkaline substances from a alkaline plant, dandelion, in ethanol and ethyl acetate solvent for 10~15 minutes.
The solution was filtered with carbon black for decolourization, but it didn't show alkaline colour with universal indicator.

So... I've got some questions to ask

1. Is dandelion alkaline?
2. If it's alkaline, is it possible to extract alakline substances or alkaloids from the plant?
3. If dandelion is not alkaline enough, then could there be any othe ralternative plant or food that can be extracted alkaline substances?
4. Is alkaloid alkaline?
5. What are the alkaline substances coming from?
6. If the simple boiling extraction doesn't work , is there any other ways that I can extract alkaline substances from the plants?

Could you explain in high school level.
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I hope this forum can also help regarding electricity science.
Need to purchase a few single cells of lipo and ni-mh battery types >> high drain >> for airsoft purpuse, and rc!

1. Would like to get anykind information to get them from any Europe dealers, wholesalers,distributors, etc?
2. Or, name of a few manufacturers companies?

Thanks in advance...

I have a covariance matrix and I am using Matlab's chol function for cholesky decomposition. However, since my matrix is not a positive definite matrix. I am getting an error. How can I figure out which correlations/covariances in the matrix are leading to the problem.

Attached file contains the matrix.

I wish to extract info from a land registry file - see info on this link.

I have a UK land registry .gml file downloaded from their site

I have installed QGIS and have managed using the menu item FILE / IMPORT VECOR DATA / COMMON IMPORT FORMATS browsed to the .gml file and opened it but all I see is View1 ( attached ). I can zoom to produce View2 & 3 ( also attached )  but I can't see how I can reveal the Polygons referred to by the Land Registry.
Due respect sir,
The we questions is that

(A×B.C)(a×b.c)=|A.a.      A.b.      A.c.  |
                           |B.a.        B.b.     B.c.  |
                           |C.a.       C.b.      C.c.   |

Sir as soon as possible plz send the solution my mail

                   Thank you
                  Your student
Scenario: bins are taken out once a week from a storage area to another location more than 20 meters away. I want to know if the bins have NOT been taken out at any given time each week.

eg if the bins are tagged and the storage area has a receiver, the receiver can tell me if the bins are in or out of storage.

I would like to tag around 4 bins only. What cheap and simple tagging solutions exist?  

I would like the receiver to connect to wifi so i can check the status remotely. The tag on the bins should be small and discrete, so as not to encourage vandalism or theft. They should also be very low power so that batteries, if the tag needs them, would need changing at most once a year. Perhaps a magnetic solution would avoid need for batteries on the bins.

The position of the bins in the storage area is not precise but would not vary by more than 2 meters.

If ax²+2hxy+by²=c²,verify that dy/dx.dx/dy=1
consider the subgroup of s4 given by G={(123),(134)}
1 what is the order of G
2 what are the orders of the elements of G, and how many elements of each order.
3 what are the orders of the subgroupsof G Give an example of a subgroup of each order.
The curve on the tab "Curve fitting graphic" in the Excel "Distansomräkningstider" attached here is almost perfect. It is only the last part that is pointing too sharply upwards. It should be more flattened out (but never turn townwards, always continue to pointing slightly upwards) from around 2500 metres or 2600 metres, which seems to be a "breaking point" for two different curves.

The context is harness racing track times for different lengths of the races with the purpose of calculating re-calulation coefficients for different lengths of the races. Index is 2140 metres (x). The software I use is CurveExpert. I received help here at EE earlier at this thread:

Is there any online tool where I can enter x and y values to get a curve diagram displayed, and then enter more x values to get exact y values calculated?

In essence, this graph consists of 2 curves, and they cross each other at around 2500 or 2600 metres. The first curve is more favouring the speed of the horse (shorter distance, which means the horse is able to run much faster due to a short distance where strength and stamina is not required), whereas the second curve is more favouring the strength, or stamina, of the horse (longer distance, which means the horse can not run so much faster the more the curve moves to the right and the distance gets longer and longer).

My reliable five values I have now are these:

x=1640; y=0.913999
x=2140; y=1
x=2640; y=1.048999
x=3140; y=1.110999
x=4000; …
I'm not sure if this is the right place to try asking this - But here goes anyway

Using a sampling pump I want to push water through a ½  or ¾  inch Sch80 PVC pipe with enough pressure to traverse 20 feet vertical and 600 feet horizontal in a minute or less. This is next to a free flowing canal. I want to sample 600 feet upstream to prepare for what will be coming in the intake. The canal runs about 15 minutes to cover the same distance . This give me a 14 minute look ahead.

I calculate that it will take about 150PSI (using 1.8 Hp) in ¾ inch pipe and about 230 psi (using 1.25 Hp) in ½ inch pipe.
That gives me about 10 ft/sec.

2 questions:
  1. I used math I am not familiar with so are my calcs even in the ballpark?
  2. Will 10 Ft/sec be a problem for PVC piping? I read somewhere that over 5ft/sec will be noisy (which is OK) and make the pipe wear badly (which is not) .

Hope you can help.
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Need details about management problems and action to solved those.
With Simple Linear Regression, is the goal to transform towards a near normal bell-shaped model?

In other words, if I find some skewness, residual autocorrelation, outliers, and heteroskedasticity in residuals, should I apply techniques to transform the data towards the ideal?

  1. Should the transformation be applied to the independent (X) variable only or both X and Y?
  2. when should this be applied to residuals only?
  3. should these techniques be applied early on to X and Y?

I applied the following:
  1. log(10) to X and the histogram looks more normal than before.
  2. "residual shift" technique which improved the autocorrelation substantially (autocorrelation now -0.045, Durbin-Watson now 2.09)
  3. excluded data outside the "InterQuartile Range (IQR)" - not sure if this did much

Hope you can help!
Thank you!

Do you happen to know of any DB/book/website/etc. where I can find a list of all known proteins and their function?

Thank you,
My plot has below dimensions . I tried but couldn't find  are
Angle <ABC=84 and  Angle <BCD=84

Please help me to find area
Chinese Calendar                                                Instructions                              
Year      From        To      Animal Sign      Element      Aspect                  Calculate the Animal sign, element and aspect based on the Chinese Calendar provided                              
1900      31-Jan-00      18-Feb-01      Rat      Metal      +Yang                                                
1901      19-Feb-01      07-Feb-02      Ox      Metal      -Yin                  Date of birth      Animal Sign      Element      Aspect            
1902      08-Feb-02      28-Jan-03      Tiger      Water      +Yang                  Jan 01, 1987                              
1903      29-Jan-03      15-Feb-04      Rabbit      Water      -Yin                  Jul 05, 1977                              
1904      16-Feb-04      03-Feb-05      Dragon      Wood      +Yang                  Nov 01, 1977                              
1905      04-Feb-05      24-Jan-06      Snake      Wood      -Yin                  Feb 02, 1978                              
1906      25-Jan-06      12-Feb-07      Horse      Fire      +Yang                  Aug 16, 1977                              
1907      13-Feb-07      01-Feb-08      Sheep      Fire      -Yin                  Dec 14, 1974                              
1908      02-Feb-08      21-Jan-09      Monkey      Earth      +Yang                  Feb 10, 1980                              
1909      22-Jan-09      09-Feb-10      Rooster      Earth      -Yin                  Jul 27, 1979                              
1910      10-Feb-10      29-Jan-11      Dog      Metal      +Yang                  Sep 13, 1980                              
1911      30-Jan-11      17-Feb-12      Pig      Metal      -Yin                  Jul 26, 1972                              
1912      18-Feb-12      05-Feb-13      Rat      Water      +Yang                  Jun 05, 1976                              
1913      06-Feb-13      25-Jan-14      Ox      Water      -Yin                  Feb 28, 1971                              
1914      26-Jan-14      13-Feb-15      Tiger      Wood      +Yang                  Aug 25, 1975                              
1915      14-Feb-15      02-Feb-16      Rabbit      Wood      -Yin                  Nov 01, 1977                              
1916      03-Feb-16      22-Jan-17      Dragon      Fire      +Yang                  Feb 01, 1979                              
1917      23-Jan-17      10-Feb-18      Snake      Fire      -Yin                  Dec 12, 1978                              
1918      11-Feb-18      31-Jan-19      Horse      Earth      +Yang                  Jul 31, 1976                              
1919      01-Feb-19      19-Feb-20      Sheep      Earth      -Yin                  Feb 14, 1977                              
1920      20-Feb-20      07-Feb-21      Monkey      Metal      +Yang                  May 18, …
how a person cannot overtake a tortoise in a race in which the tortoise was given an head start....


Math / Science

The Math / Science topic primarily includes discussions of mathematics, physics, statistics and economic analysis, but also biology, chemistry and other sciences.