What do phase dots on an inductor mean?

Question: I have a SEPIC supply with coupled inductors. The inductors have phase dots. What do these "phase dots" mean? Is it important to have the phase dot in the same place?
Comment: relevant: http://electronics.stackexchange.com/questions/66708/dots-in-a-transformer-symbol
Answer: If we're thinking about same thing, then dots show relation between coils. Here's an article about that.
If I get the dot relation correctly (and I'm not sure that I do), if current is going into the dot on one side of the inductor and the other dot is on the same side of the inductor, that means that current is going into the dot on the other side too.
How important it is to have dots in the same place is up to design of the circuit. In some cases it may not be relevant, but often it is important to take it into account.
Comment: dot orientation matters, for example, when transformers are part of feedback circuits in oscillators.
Comment: @JustJeff Indeed! On the other hand, if the load was just a simple resistor, it wouldn't matter.
Answer: The dots just indicate the polarity of the windings on the schematic.
Currents entering on the dotted ends of the windings will produce magnetic flux in the same direction, whereas if you have current entering one dotted end, and leaving another dotted end, the currents will produce opposing flux.
If you're looking at something like a power supply schematic, the dots show you the ends of the coils that have the same phase angle.
Answer: I think I can help.
The dot indicates the outside wire of the inductor, particularly for inductors that are wound on a ferrite spool or bobbin. This can be useful for minimizing unwanted emissions. For example, if you are designing a switching converter (buck, boost, or SEPIC), one end of the inductor(s) is normally tied to a DC power rail while the other end is switched up and down. If you tie the "dot" end of the inductor to the DC rail, the inner windings of the inductor will be doing most of the voltage swinging, and the outer layers will help shield them from radiating.
In a SEPIC converter, inductor coupling is optional. The only way to couple the inductors is to wind them on the same core. If you're buying single inductors off-the-shelf, your design is UNcoupled and you want to make sure the inductors do not interfere with one another. For uncoupled inductors, tie the dotted end of the series inductor to the input voltage and tie the dotted end of the parallel inductor to ground. That will minimize emissions and unwanted coupling between the two inductors.
Film-type capacitors are marked the same way. Film capacitors have no voltage polarity restrictions (unlike electrolytics and tantalums), but they still have a polarity mark on them. Film capacitors are made by wrapping foil and insulating film (or metallized film) like a roll of toilet paper, and the dot indicates the outer layer of that winding. Tie the dotted end to DC, and the capacitor is partially shelf-shielding.
Comment: Nice. This should be the accepted answer.
Answer: Normally we apply AC voltage on the (input) primary coil of the transformer and we have an (approximately) resistive load on each (output) secondary coil of the transformer.
In that case, the dotted end of every coil will reach the positive peak voltage relative to the non-dotted end of that coil at (approximately) the same time.
Also at that same instant current will be flowing into the dotted end of the primary coil and current will be flowing out of the dotted end of each secondary coil.
The dots describe which way each coil was wound.
If I take a CAT5 cable and wind it around a ferrite core, each wire-end at one end of the CAT5 cable is dotted. Each wire-end at the other end of the cable is not-dotted.
I honestly don't know if dot orientation makes any difference for a SEPIC converter.
I know that the dots are important in the very similar "Coupled Inductor Cuk Converter" and "Integrated Magnetics Cuk Converter" ( The Four Topologies  ).
If one accidentally swaps the two ends of a coil in that converter, you get increased (worse) ripple on the input or output or both.
Answer: In short and oversimplifying:
The dots indicate which winding terminals have the same phases of induced AC voltages. That assumes you're driving one winding and others are not loaded.
Answer: In support of what Marc & Jose said, the inductor dot indicates where the wire starts to be rolled on the core. Because that dot point is below the rest of the windings, it is shielded by them. In a SEPIC or other switch mode designs, the SW node is basically your noise source, and you want to make sure you wire the shielded dot point to your noisy SW node.
SOURCE: Larsen at ADI Engineer Zone
Emissions Example #1: The URL in Jose's post is now a dead link, but while searching the Wurth website, I found that the middle section of this blog entry emphasizes the importance of putting the inductor dots toward the switch node. It provides E-field & H-field emissions graphs.
Emissions Example #2: AnalogDialogue shows several emissions graphs from both inductor orientations, and explains that the polarization indicator is a line (not a dot) on some Coilcraft inductors. The article goes on to explain what to do when no polarization indicator is present.
Answer: Wurth indicates the dot is the start of the winding (which makes it the inside winding) and therefore the dot should be placed at the switching node for the reasons Marc mentioned above. I don't know if there's a convention for this, but if there isn't, I would ask the manufacturer what the dot indicates when used with switchers.
https://www.we-online.de/web/en/passive_components_custom_magnetics/blog_pbcm/blog_detail_electronics_in_action_109450.php

What do phase dots on an inductor mean?


Can I use Surface Pro 4 and Illustrator CS6?

Question: I recently bought the new Surface Pro 4 with 8 GB RAM and 256 GB SSD. I installed my CS6 Standard Suite yesterday and I was quite impressed how fast illustrator and Co. opened. Unhappily, the pen does not seem to interact with the programs, so there is no pressure sensitivity (which works quite well with One Note or Fresh Paint). Any solution?
Comment: What tool are you using?
Answer: You can use it, but unfortunately only the Creative Cloud version of Photoshop and Illustrator are optimized for pen use. I went to Adobe Max 2014 and I learned that there is actually a different "version" of those two apps built specifically for the Surface, with larger buttons, streamlined menus and tools that work great with the pen. I have used them on my Surface Pro 3 during the trial and they did work really well.
Comment: The same here. When I put my touch enabled laptop in tablet mode in Win10, Ai and Ps automatically switch to touch layout. You can find it in the menu under *Workspaces* I believe.


Transform SPOT5 images to natural color images

Question: We're currently using PixelSense to convert raw SPOT5 images to natural color ones for display and printing. Do you know a good algorithm to perform the same task as we want to ingest raw images in an image server and provide an image service with on the fly natural color conversion.
Answer: An option is to perform these steps:

generate a synthetic blue channel
balance the colors by outlier removal through analysing the channel historgrams. For a GPL'ed approach, see here
then create the RGB composite

Concerning the generating of a synthetic blue channel:
Since I don't have SPOT5 data here, I cannot make a test. But I found this formula (Knudsen):
<code>Blue_synth = 0.70 × Green + 0.24 × Red - 0.14 × NIR
</code>
Comment: The first step is where the magic lies, I guess. Care to elaborate please ?
Comment: I have edited my previous answer, see above.
Answer: If you are using ESRI software; check out this thread: http://forums.esri.com/Thread.asp?c=93&f=982&t=271727&mc=10#msgid841178


Bone weights won't show when selecting bone directly

Question: I've used rigify to set up a rig, I've gone through all the steps to complete the rig. I have the bone weight vertex groups from the rig, which show fine when selecting the group directly. I have the metarig hidden so I'm not highlighting the wrong one. But when doing normal weight-painting of rig+model and then ctrl-clicking a bone, they all show as blank. This is how it's normally done and it's EXACTLY what tutorials say to do, down to following their exact keypresses. They all show as pure magenta unless I click somewhere. I've weight-painted a few times before so I know how it should work, but I cannot for the life of me understand what's going on or why this is a problem.
Yes, the rig controls the model, everything seems to have worked, there was no error that I saw. I simply can't show weights by clicking the bones in weight-painting mode.
I'm at my wit's end due to a complete lack of any information on anything like this.
Please help me.
Blender3.1.0 for note.
Answer: It sounds like you've selected a bone with an property that disallows geometry deformation. All deformable bones have a prefix of DEF- and they appear when turning on the 30th armature visible layer.


Accessing Files in Other Users FTP Folder?

Question: I have a wifi security camera that writes to an FTP server located on a 16.04 LTS system.  I create the user in Ubuntu and that automatically creates a home folder.  When I create the user in the ftp server, it assigns a folder in the home folder for accepting the video files automatically triggered by the cameras motion sensing.  All that works.
However, in order to see and/ or delete the video files I need to be logged on under the camera's user name.  I would like view and delete access when logged in under my primary name.  I tried running chmod 777 * from the folder holding the files but that killed everyone's access to the folder, including the camera.  I could not correct so deleted the user in Ubuntu and recreated so I'm now back at the same state in the paragraph above.
Any suggestions on this?  I also want to create an auto run type script to delete files after X days so am concerned how the user rights will affect that.
Answer: I had no responses so I'm wondering if this is a dead forum.  Is there a better place to post questions?
I did find something that worked by using groups.  see the link
how to give read, write and modify access to folders and files in my home directory mutually to other users on same computer?


How can I cancel a pending payment in App Store?

Question: I have accidentally subscribed yearly to an app, and now I removed the subscription but they're still trying to take the payment (no sufficient funds). Can I cancel the payment anyhow?
Answer: If you cancelled the subscription soon after you subscribed, and you explain it was an accident no payment should be taken.
Bear in mind that if you had a free trial before the subscription, and you don't cancel 24 hours before the end of the free trial, you may still be charged.

Some subscriptions might offer a discounted or free trial. If you don't cancel more than 24 hours before your renewal date, your subscription might renew.

(Source)
Make sure you follow View, change, or cancel your subscriptions.
Additionally, you can go to Apple's official Report a Problem. This is specifically for subscriptions.


How to place an object higher on the plane via Python?

Question: I need to make an image in which there are two objects when one of them is located regularly on the plane but the second is actually a bit on top of the first one when they do not touch each other. It is actually not realistic because the second object is hung in the 'air' without any support. For example, in the attached image, the sphere is located (not realistically) on top of the cube.
I tried to use the function of bpy.ops.transform.translate(value=(x, y, scale)), but none of its parameters controls the height of objects.
Do you have an idea how can I make it?
Comment: Please clarify your specific problem or provide additional details to highlight exactly what you need. As it's currently written, it's hard to tell exactly what you're asking.
Answer: Just a cheap solution:
<code>import bpy

# need 'Cube' and 'Sphere'
cube = bpy.data.objects['Cube']
sphere = bpy.data.objects['Sphere']

for idx in range(3):
    sphere.location[idx] = cube.location[idx]   # loc x,y,z is same

sphere.location[2] += (cube.dimensions[2]/2) + (sphere.dimensions[2]/2) # move sphere to top of cube
</code>
Comment: Thank you very much! it is exactly what I needed.


Is possible, feasible or even recommended (if possible), to change the title or the keywords of a page using Google Tag Manager?

Question: Does Google Tag Manager could or should be used to change content in a page, like title, keywords or description?
Comment: You can edit the tags, but it seems unlikely that this will affect SEO positively (it might be seen as an attempt at cloaking, in that case the effect would be negative). Unlike in earlier times Google now renders some Javascript when it crawls the page, but I doubt it'll catch metatags changed via JS. However the only definitive way would be to test this - I don't think anybody has done a "scientific" test on this yet.
Answer: Google is improving it's ability to read javascript rendered pages. However, it's not to a point you can rely on it for inserting critical headers.
Here is one such article on researching this possibility.
For now, you need to have the important information embedded into the HTML when it's served. There is also the chance that javascript rendered changes in content will be seen as cloaking - although it is commonly used for A/B testing.
Answer: I am not sure if the GTM is useful in this case. The video from Google will give you a clue where you can use the tag for: https://youtu.be/7FXbsCWsEi8 .
Comment: I see, this idea came from a client, saying that he wants a site where he can change the title and others meta tag through Tag Manager, as far as i know, even if is possible it will change things using javascript and change meta tags with javascript will impact SEO.


find the exact error in solidity transaction programmatically

Question: I know we can detect that the transaction is going to be failed with the "Out of gas" warning beforehand but is it possible to find the exact error before sending it to the blockchain. How can we simulate a transaction as its mined (failed) and find the exact error (or line of code) where it failed?
Answer: So if I understand correctly you want to detect this kind of errors in advance, without actually sending the transaction to the real blockchain.
Whether the transaction succeeds or not may possibly depend on the contract state. Therefore it's not enough simply to take the same contract offline and test that even if that might get you quite far. So what you can do it take the entire blockchain with its state, run it locally offline and execute transactions against it. Then you can roll back transactions (continue mining from a certain block) as you wish.
Technically I'm not exactly sure how this should be accomplised even if I know it can be done. Basically if you have a full synchronized node you have all the data you need - you just need to change it to run locally in your node instead of connecting to other peers.


i would like to control one z-wave wall switch with two remote controls

Question: I would like to control one z-wave wall switch with two remote controls.  If there's an issue using two z-wave remotes, then I would like to clone the on and off signal to a second learning RF remote.
Answer: You cannot clone on and of with a learning remote z-wave has some sort of rotating code I'm sure, just like you can't clone a garage door remote with just the remote.
You should be able to pair a second controller to the network, but I am not an expert.
Answer: Just buy the Aeon Zwave minimote and pair it to your hub.  You can then program the four buttons on each to control switches.  As far as I know, you can use different remotes to control the same switch.


resampling data in 2 subset to eqully

Question: Could you help me a little bit
i have 2 subset binary image curve A and B ,How i resampling data A or B to Equally.
For Example
curve A,   {(1,1),(1,2),(1,3),(1,4),(1,5)}
curve B,   {(5,5),(5,4),(5,3)}
i would like resampling the number of element B to 5 for equally A
B( resampling )==>  {(5,5),(5,4.5),(5,4),(5,3.5),(5,3)}
i done to implement this method in c++.
but I do not sure that is call linear interplolation method
and another problem i do not know how to write this method equally A and B in term of Math formular or in term of geometry discrete?
thank you very much
kitti
Answer: You can use Lagrange interpolation.

resampling data in 2 subset to eqully


In an O-H bond, will polarity increase/decrease if some of the electron density on the oxygen atom is reduced?

Question: Like when an e- withdrawing group (sp2 carbon) is attached to oxygen of the OH bond, it attracts the electrons. So will the polarity of the OH bond increase or decrease?
Answer: The polarity on the oxygen atom will decrease. This is because of the sp2 hybridised carbon atom which is highly electronegative. This will result in a decreased polarity in the OH bond and hence it will disassociate more easily in solvents such as water. One example of this effect is the increased acidity of phenol compared to most alcohols. This is because the OH is bonded to sp2 hybridised carbon in phenol and hence will disassociate in water easily when compared to normal alcohols.
Answer: Yes, polarity can be changed. Example, between alcohol and phenol the O-H polarity is more in phenol nd less in alcohol. It is due to the extent of attraction of electron by oxygen from hydrogen which is more in phenol.
Answer: The electron density on oxygen decreasing will result in tye polarity of the OH bond increasing. This will increase the acidic strength of phenols when comapred to to alcohols, where the OH group is attached to the sp3 carbon.


Getting thumbnail data for documents with CSOM / API

Question: In our project we're trying to integrate with SharePoint Online using SharePoint App-Only authentication method and client-side object model (CSOM) to retrieve data. This solution seems to be working fine but the problems start when we're trying to get 'Thumbnail' image for the document. The default way of getting document data with CSOM never returns any thumbnail data. Instead, we've started using SharePoint's API method /_layouts/15/getpreview.ashx. By default, it doesn't return any thumbnail data when used with the same access token as we used for CSOM but when used in browser from the context of user that is logged in Sharepoint Online platform (i.e. authenticated via cookies) it works fine.  From now on (after getting this specific thumbnail in a browser for the first time) it will also work from our integration (authenticated with bearer token).
Any ideas what can be the cause of this and how to fix it? Are there better ways to get thumbnail data from the document in SharePoint?
Answer: @know,
MS Graph API provides an endpoint that could request document thumbnail.

GET /me/drive/items/{item-id}/thumbnails

BR


IIS self-signed > 1 year

Question: In IIS, we can create a self-signed certificate. The expiration of the certificate defaults to one year. Does anyone know whether this can be changed for example via the "Configuration Editor"?
Answer: IIS doesn't do anything special when generating a self-signed certificate so you can use and tool for that.
For instance, you can use Powershell. This one-liner will create a self-signed certificate for the DNS name test valid for 5 years, with no password and place it into the local machine certificate store (it requires elevation).
New-SelfSignedCertificate -DnsName "test" -notAfter $([datetime]::now.AddYears(5)) -CertStoreLocation cert:\Localmachin\My

IIS self-signed > 1 year


How can I save wet cookie dough

Question: I accidentally added 2/3 cup milk instead of 1/3 to a cookie dough. Now dough is too moist. What can I add to absorb the moisture?
Comment: I haven't actually tried this, hence comment and not answer, but possibly, baking the dough as one big cookie could work. Lower the oven temperature by at least 25 degrees (F) and ignore the timing guidelines: just bake until the middle looks set. You'll get something more cake-like than cookie-like, but it ought to be nice and moist. :)
Comment: Doesn't answer the actual question but there is another way to salvage the dough: Depending on what kind of cookies you have you could add more milk (and probably more "wet" ingredients like eggs, sugar; baking powder if needed to) until you get a butter cake batter ...
https://www.seriouseats.com/recipes/2017/05/classic-vanilla-butter-cake-recipe.html
... in case you don't have any flour left for doubling the cookie receipe.
Answer: You could go ahead and add each of the other ingredients (other than the milk) again, doubling the recipe.
If you really want to get fussy, you probably should follow the recipe instructions regarding "creaming butter and sugars"...etc. with that second round of ingredients, but honeslty cookies aren't that particular about technique, so I would just dump them in and mix-em up. Your result should be quite reasonable.
Comment: I would add that skipping the 'creaming...' would depend entirely on what kind of cookies you are making. DON'T skip that step for sugar cookies, snickerdoodles, butter cookies. For peanut butter or chocolate chip your mileage may vary.
Comment: I'm not sure if just doubling the recipe works (it depends on the cookies). In case baking soda is the sole leavening agent: If too much moisture was added at the beginning I'd think this would lead the baking soda act too early and thus resulting flat cookies. If (double-acting) baking powder is used I'd be more confident that the cookies won't be very dense.
Answer: You have several options:

The simplest solution: add flour (and a bit of sugar).
The true-to-the-recipe solution: double the rest of the ingredients.
The "I am out of flour and sugar" solution: spread the mix out in the oven (at a low temperature) and dry it, mixing it up regularly to even out the temperature.
Comment: @Minix not with cookie dough (barely made them) but with other very/too wet doughs such as bread or protein cakes. Flavour was not much impacted, texture might be depending on your recipe.
Comment: Have you tried the third option and can share your experience? It seems straight forward, but I have a hard time believing it would work (it seems to easy?).
Comment: I'm skeptical about that third option, too.  It seems like the dough would start to cook at least a little, which I can't help but think would severely impact the texture if not flavor of the finished cookies.  If drying the dough out is the goal, I might refrigerate it uncovered for a while.
Comment: *a bit of sugar* and a pinch of salt,  lest they come out tasting like cardboard.

How can I save wet cookie dough


Linear regression without Y variable

Question: I want to perform a linear regression model on a dataset with some bestseller books, the dataset contains 550 the bestseller books - I want to create a lm() model where I predict the variables that are most influential when it comes to becoming a bestseller, however, there is no obvious Y variable in the dataset since all the books are bestsellers. How would you solve that? Would you add a Y variable, and if yes, which? Or is there another solution?
Comment: You cannot figure out why bestseller books are bestsellers... using only
bestseller books, there is nothing to compare to. You would need to have preferably an equal amount of both type of books in your data, bestsellers and non-bestsellers, and then your y could be 1 or 0.
Comment: Are you able to share a sample of the data eg using `dput` in R or host it online? Would make it easier to visualise. Even in a bestseller dataset there may be a disparity in how many they've sold
Comment: @user2974951 Since most books are not bestsellers, I would actually want to have more of them in the dataset. Preferably, the dataset should be a random sample (of sufficient size).
Answer: @user2974951 addresses the problem here.  In order to determine which variables best predict bestselling books, you'd need to better define your population under study, which would have to include best-selling books in addition to non-best-selling books.  For example, you may be able to obtain a list of books published and made available to the library of Congress in a given year.  You would then need to cross-reference that list with, say the New York Times Best Seller list (you'll need to define "best-selling" more carefully too because there are many "best-seller" lists).  Once you have identified best sellers, one approach is to use logistic regression.  Using this approach, you could code a variable, say, best_seller, as 1 if the book is a best-seller and 0 otherwise.
Once your dataset is properly coded and includes observations from both non-best sellers and best-sellers there are a number of approaches for determining the "most influential" variables in predicting best-sellers.  You could use methods like simple regression with standardized coefficients, or better yet logistic regression.  There are a number of other methods in machine learning that may be even better suited for this task such as the xgboost algorithms like adaboost.  What you are after is essentially called variable importance or feature importance in the machine learning communities.  If you search Cross-Validated on these terms, you'll find a number of methods that you can try out.

Linear regression without Y variable


Solaris not seeing FC volume

Question: We recently replaced a failed controller in an AL connected RAID. I wasn't the one that replaced the controller, but apparently when the new controller was installed something weird happened with the channel IDs/LUNs, but retained the volume configuration. Right now I have it on a single controller, with the channel IDs and LUNs correctly configured, but Solaris isn't seeing the volume (/dev/dsk doesn't have device links for the volumes), even after a boot -r. cfgadm -al shows connected and unconfigured. I tried cfgadm -c c7 configure, but this did not work. fcinfo hba-port shows the connection as offline. Any ideas?
Comment: I'm a little unclear about the architecture- what type of controller is it? Local raid card in the server, or standalone shared storage?
Answer: Try cycling the port

cfgadm -c disconnect
cfgadm -c connect
cfgadm -c configure

Solaris not seeing FC volume


How many more hours of sun will my plants get in the summer

Question: We just moved to a new place so I am not sure what spots get what amount of sun during the summer hours. I found a website to calculate the angle the sun will be during any given month but I'm not sure how to factor in the height of the house and fences to figure if the spot will get at least 6 hours.  I am in zone 9b.
Comment: which way does the area you want to work out face, north,south etc? Use a compass (there should be one on your phone) with your back to the house when you do it ...and add that info to your question please
Comment: A geographic location would be helpful as would the reason you want to know (how accurate does the answer need to be?)
Comment: Zone 9b.  Shoot, you've nothing to worry about unless this is winter in your area.  Is your garden in the shade of the house?  East or west shade?  Truly if you are in spring and summer nothing to worry about except planting in the shade.  A little shade is fine if it is during the summer and from the west late afternoons.  Actually a good thing.  If you were a lower zone not so much.  Send more information such as zone, what it is you are growing, do you have high winds...as much detail as you are able.
Comment: I don't know what "zone 9b" means but the biggest variable is your latitude.  Also, all the obvious things like which side of the house your garden is on, the height of the house, the distance between the house and the garden, whether there are any hills nearby and how big they are.  It's impossible to answer your question without these details.
Comment: @DavidWallace zone 9b is referring to the United States Department of Agriculture (USDA) Plant Hardiness Zones see http://planthardiness.ars.usda.gov/PHZMWeb/ for more details. It runs in reverse (higher zone = hotter) to Royal Horticultural Society (RHS) Hardiness Ratings (higher rating = hardier) and is map based rather than plant based which the RHS ratings are. The RHS rightly shy away from a map based system as microclimate can have a massive impact on the plant that will grow in a particular area. USDA zone is not relevant here as it does not indicate latitude or aspect.
Comment: Yeah I think it is probably too complicated and I will just have to guesstimate. I am in Sacramento CA.
Answer: Unless you want to spend a long time doing calculations, quickly modelling your house and trees in a georeferenced SketchUp model would be a good start. The shadows can be set for the time of year etc and give a good approximation that should be suitable for your needs. Having done this you will start to realise the question is a lot more complex than doing a quick calculation based on the angle of the Sun and height of your house...


How to access a file's properties on Windows?

Question: Last time I asked a similar question but that was about svn related versioning info. Now I am wondering how to query windows "File version" attribute about eg. a dll. I payed attention to wmi and win32file modules as well without success.
Answer: Here is a function which reads all file attributes as a dictionary:
import win32api

#==============================================================================
def getFileProperties(fname):
#==============================================================================
    """
    Read all properties of the given file return them as a dictionary.
    """
    propNames = ('Comments', 'InternalName', 'ProductName',
        'CompanyName', 'LegalCopyright', 'ProductVersion',
        'FileDescription', 'LegalTrademarks', 'PrivateBuild',
        'FileVersion', 'OriginalFilename', 'SpecialBuild')

    props = {'FixedFileInfo': None, 'StringFileInfo': None, 'FileVersion': None}

    try:
        # backslash as parm returns dictionary of numeric info corresponding to VS_FIXEDFILEINFO struc
        fixedInfo = win32api.GetFileVersionInfo(fname, '\\')
        props['FixedFileInfo'] = fixedInfo
        props['FileVersion'] = "%d.%d.%d.%d" % (fixedInfo['FileVersionMS'] / 65536,
                fixedInfo['FileVersionMS'] % 65536, fixedInfo['FileVersionLS'] / 65536,
                fixedInfo['FileVersionLS'] % 65536)

        # \VarFileInfo\Translation returns list of available (language, codepage)
        # pairs that can be used to retreive string info. We are using only the first pair.
        lang, codepage = win32api.GetFileVersionInfo(fname, '\\VarFileInfo\\Translation')[0]

        # any other must be of the form \StringfileInfo\%04X%04X\parm_name, middle
        # two are language/codepage pair returned from above

        strInfo = {}
        for propName in propNames:
            strInfoPath = u'\\StringFileInfo\\%04X%04X\\%s' % (lang, codepage, propName)
            ## print str_info
            strInfo[propName] = win32api.GetFileVersionInfo(fname, strInfoPath)

        props['StringFileInfo'] = strInfo
    except:
        pass

    return props

Comment: Wow, great work. How did you even find out the StringFileInfo stuff.. that's what I need. thanks a lot.
Comment: For those who care, 65536 is half a DWORD (2 **16)
Comment: This is the best approach to the problem I've found so far. If anyone knows where to find documentation to back this up, it would make a great addition to this answer (I've had a look but couldn't find anything authoritative).
Comment: Only works for exe and dll.
Answer: Better to add a try/except in case the file has no version number attribute.
filever.py

from win32api import GetFileVersionInfo, LOWORD, HIWORD

def get_version_number (filename):
    try:
        info = GetFileVersionInfo (filename, "\\")
        ms = info['FileVersionMS']
        ls = info['FileVersionLS']
        return HIWORD (ms), LOWORD (ms), HIWORD (ls), LOWORD (ls)
    except:
        return 0,0,0,0

if __name__ == '__main__':
  import os
  filename = os.environ["COMSPEC"]
  print ".".join ([str (i) for i in get_version_number (filename)])

yourscript.py:

import os,filever

myPath="C:\\path\\to\\check"

for root, dirs, files in os.walk(myPath):
    for file in files:
        file = file.lower() # Convert .EXE to .exe so next line works
        if (file.count('.exe') or file.count('.dll')): # Check only exe or dll files
            fullPathToFile=os.path.join(root,file)
            major,minor,subminor,revision=filever.get_version_number(fullPathToFile)
            print "Filename: %s \t Version: %s.%s.%s.%s" % (file,major,minor,subminor,revision)

Cheers!
Answer: You can use the pyWin32 module from https://github.com/mhammond/pywin32:
from win32com.client import Dispatch

ver_parser = Dispatch('Scripting.FileSystemObject')
info = ver_parser.GetFileVersion(path)

if info == 'No Version Information Available':
    info = None

Comment: Is there any way I can get the file description as well ? I did not see any method in FileSystemObject which does that :(
Comment: After hours of frustration and struggle with pywin32, looks like all I needed was this....Thank you
Comment: Only works for exe and dll.
Answer: Here is a version that also works in non-Windows environments, using the pefile module:
import pefile

def LOWORD(dword):
    return dword & 0x0000ffff
def HIWORD(dword):
    return dword >> 16
def get_product_version(path):

    pe = pefile.PE(path)
    #print PE.dump_info()

    ms = pe.VS_FIXEDFILEINFO.ProductVersionMS
    ls = pe.VS_FIXEDFILEINFO.ProductVersionLS
    return (HIWORD (ms), LOWORD (ms), HIWORD (ls), LOWORD (ls))

if __name__ == "__main__":
    import sys
    try:
        print "%d.%d.%d.%d" % get_product_version(sys.argv[1])
    except:
        print "Version info not available. Maybe the file is not a Windows executable"

Comment: I figured out from the source that you can cut that 10s down to 1s/2s by parsing only the resources directory, woo!:
`pe = pefile.PE(path, fast_load=True)
pe.parse_data_directories(directories=[pefile.DIRECTORY_ENTRY['IMAGE_DIRECTORY_ENTRY_RESOURCE']])`
Comment: I find this to the job perfectly, but it takes over 10s to do it on a 30mb exe :(
Comment: pe.VS_FIXEDFILEINFO now returns a list, so you need to change to `ms = pe.VS_FIXEDFILEINFO[0].ProductVersionMS
ls = pe.VS_FIXEDFILEINFO[0].ProductVersionLS`

Also: Steve's suggestion is a massive improvement speed-wise, and is a simple plug-and-play change to syntaxaire's example.
Comment: Nice! I wanted to suggest something like that.
Answer: I found that the only cross-platform answer (using pefile) couldn't find the version string I was looking for, which is the one shown in the 'Details' tab of the 'View properties' of a .DLL file on Windows. However, this code, based on the dump_info() function in pefile, is able to find those attributes, which include original filename, copyright, company name, and file and product versions.
You may need to replace encoding with a different encoding if they are not encoded using UTF-8.
import pefile

PATH_TO_FILE = 'C:\...'
pe = pefile.PE(PATH_TO_FILE)

if hasattr(pe, 'VS_VERSIONINFO'):
    for idx in range(len(pe.VS_VERSIONINFO)):
        if hasattr(pe, 'FileInfo') and len(pe.FileInfo) > idx:
            for entry in pe.FileInfo[idx]:
                if hasattr(entry, 'StringTable'):
                    for st_entry in entry.StringTable:
                        for str_entry in sorted(list(st_entry.entries.items())):
                            print('{0}: {1}'.format(
                                str_entry[0].decode('utf-8', 'backslashreplace'),
                                str_entry[1].decode('utf-8', 'backslashreplace')))

Answer: Here's a working version of marsh's answer, only using the standard library. Use it like get_version_string(file, "FileVersion"). See VerQueryValueW() for the valid version strings.
from ctypes import *

# returns the requested version information from the given file
#
# `what` is one of the predefined version information strings, such as
# "FileVersion" or "CompanyName"
#
# `language` should be an 8-character string combining both the language and
# codepage (such as "040904b0"); if None, the first language in the translation
# table is used instead
#
def get_version_string(filename, what, language=None):
    # VerQueryValue() returns an array of that for VarFileInfo\Translation
    #
    class LANGANDCODEPAGE(Structure):
        _fields_ = [
            ("wLanguage", c_uint16),
            ("wCodePage", c_uint16)]

    wstr_file = wstring_at(filename)

    # getting the size in bytes of the file version info buffer
    size = windll.version.GetFileVersionInfoSizeW(wstr_file, None)
    if size == 0:
        raise WinError()

    buffer = create_string_buffer(size)

    # getting the file version info data
    if windll.version.GetFileVersionInfoW(wstr_file, None, size, buffer) == 0:
        raise WinError()

    # VerQueryValue() wants a pointer to a void* and DWORD; used both for
    # getting the default language (if necessary) and getting the actual data
    # below
    value = c_void_p(0)
    value_size = c_uint(0)

    if language is None:
        # file version information can contain much more than the version
        # number (copyright, application name, etc.) and these are all
        # translatable
        #
        # the following arbitrarily gets the first language and codepage from
        # the list
        ret = windll.version.VerQueryValueW(
            buffer, wstring_at(r"\VarFileInfo\Translation"),
            byref(value), byref(value_size))

        if ret == 0:
            raise WinError()

        # value points to a byte inside buffer, value_size is the size in bytes
        # of that particular section

        # casting the void* to a LANGANDCODEPAGE*
        lcp = cast(value, POINTER(LANGANDCODEPAGE))

        # formatting language and codepage to something like "040904b0"
        language = "{0:04x}{1:04x}".format(
            lcp.contents.wLanguage, lcp.contents.wCodePage)

    # getting the actual data
    res = windll.version.VerQueryValueW(
        buffer, wstring_at("\\StringFileInfo\\" + language + "\\" + what),
        byref(value), byref(value_size))

    if res == 0:
        raise WinError()

    # value points to a string of value_size characters, minus one for the
    # terminating null
    return wstring_at(value.value, value_size.value - 1)

Comment: At return you can pass (value_size.value -1) because now you get one null character at the end of string.
Comment: Works very well, thank you. I don't understand why something like this is not part of the standard library. It shouldn't be necessary to load extra modules or write elaborate functions just to perform basic file operations!
Answer: I found this solution at "timgolden" site. Works fine.
from win32api import GetFileVersionInfo, LOWORD, HIWORD

def get_version_number (filename):
  info = GetFileVersionInfo (filename, "\\")
  ms = info['FileVersionMS']
  ls = info['FileVersionLS']
  return HIWORD (ms), LOWORD (ms), HIWORD (ls), LOWORD (ls)

if __name__ == '__main__':
  import os
  filename = os.environ["COMSPEC"]
  print ".".join ([str (i) for i in get_version_number (filename)])

Comment: Nice! Though this requires you to install `pywin32`
Comment: `NameError: name 'HIWORD' is not defined`
Answer: Here is a version that does not require any additional libraries. I could not use win32api like everyone had suggested:
From: https://mail.python.org/pipermail//python-list/2006-November/402797.html
Only copied here in case the original goes missing.
import array
from ctypes import *

def get_file_info(filename, info):
    """
    Extract information from a file.
    """
    # Get size needed for buffer (0 if no info)
    size = windll.version.GetFileVersionInfoSizeA(filename, None)
    # If no info in file -> empty string
    if not size:
        return ''
    # Create buffer
    res = create_string_buffer(size)
    # Load file informations into buffer res
    windll.version.GetFileVersionInfoA(filename, None, size, res)
    r = c_uint()
    l = c_uint()
    # Look for codepages
    windll.version.VerQueryValueA(res, '\\VarFileInfo\\Translation',
                                  byref(r), byref(l))
    # If no codepage -> empty string
    if not l.value:
        return ''
    # Take the first codepage (what else ?)
    codepages = array.array('H', string_at(r.value, l.value))
    codepage = tuple(codepages[:2].tolist())
    # Extract information
    windll.version.VerQueryValueA(res, ('\\StringFileInfo\\%04x%04x\\'
+ info) % codepage,
                                        byref(r), byref(l))
    return string_at(r.value, l.value)

Used like so:
   print get_file_info(r'C:\WINDOWS\system32\calc.exe', 'FileVersion')

Comment: `WindowsError: exception: access violation reading 0x0000000082E47858` when getting the codepages. `string_at(r.value, l.value)` fails there :(


How to break the tie of SO and CS SE over an on-topic question for both?

Question: Looking at computational-geometry tag wiki on SO and CS SE, I am not able to differentiate between their purposes. I find theoretical questions(asking for an algorithm) in both SO and CS SE under this tag. For example, I have asked a question here but later I realized that SO also permits such questions on computational geometry so now I am a bit confused as to how to decide where to post.
Comment: @Pranav those are 2 different questions then, you should propose your feature in another question and make this question reflect your title about where to ask.  But before you propose your feature, I think tag hierarchical features have been proposed in the past, so you may want to do some research into previous discussions before proposing something new
Comment: I'm not sure I understand your question. You are proposing a *cross-site tag hierarchy*? What would that look like? Who would maintain it? And what would be the purpose? Why not just ask your question on whichever site you want, as long as it is on-topic?
Comment: @CodyGray "...Why not just ask your question on whichever site you want, as long as it is on-topic?". This is exactly my current problem in context of **computational-geometry** tag. I find my question to be _on topic_ for both SO and CS SE(based on their tag wikis and question asked by others there).
Comment: Okay, so...what's the question/issue to be discussed here?
Comment: I want to be sure on where to post my question. And to avoid such confusions only I thought of proposing organizing tags in form of hierarchy(I completely agree it will take very large effort).
Answer: Since your question is not about code you've written, I'd say it's more on-topic on the Computer Science beta site where you posted it.
In cases where a question would seem to fit equally on two sites, post it on the site where it's more likely to get answered. You can look at the tag info pages on SO and CS to get a rough idea of that likelihood. (You also have to take into account the size of the communities, and how active the top answerers in your tags are.)


Building a data frame and matrix for citation network

Question: I have a question about how to create a matrix that will take the lists defined below and make them the entries for the columns and rows. My data involves two lists: one lists originals sources (or papers) and the other lists those sources' individual citations.
The code is done in RStudio.
A sample of my original dataset looks like this:

<code> # List all the sources
 sources.vertices.levels <- cit.total$Sources
 sources.vertices <- (as.character(sources.vertices.levels))

 citation.edges.levels <- cit.total$Citations
 citation.edges <- (as.character(citation.edges.levels))

 # Break up the factors into character lists
 list.sources <- levels(sources.vertices.levels)
 list.citations <- levels(citation.edges.levels)
</code>
Below I have created an empty matrix (50X1497). I would like to make the row names be each individual source, and the columns be each individual citation.
Also I am lost on how to create a binary matrix that matches each individual source (from the rows) to the individual citations (to the columns).
<code> # Building an aggregate matrix
 matrix.network <- matrix(cit.citations,ncol=1497, nrow=50)
</code>
An example of what kind of matrix I want to do is below:
Answer: Are the 1s and 0s only to indicate that the source matches the citation? If so, try this :
<code>library(tidyverse); library(magrittr)
cit.total %>%
mutate(score = 1) %>% # so that all 'matches' in your original data frame are tagged '1'
spread("Citations", "score", fill = 0) # each source and citation pair gets a number, 1 if the match exists, 0 if it doesn't
</code>


What was the actual duration of Mahabharata battle?

Question: Battle of Mahabharata is a historical fact. There are differences in opinion about the duration of the battle. Want to know the duration thereof.
Answer: As per Mahabharata: Adi Parva, the great war of Mahabharata happened for 18 days :

Bhishma acquainted with choice of weapons, fought for ten days. Drona protected the Kaurava Vahinis for five days. Karna the desolator of hostile armies fought for two days; and Salya for half a day. After that lasted for half a day the encounter with clubs between Duryodhana and Bhima. At the close of that day, Aswatthaman and Kripa destroyed the army of Yudishthira in the night while sleeping without suspicion of danger. ~Mahabharata: Adi Parva

As you can see above, Aswatthama and Kripa destroyed Pandavas army in night after the close of 18th day.
Answer: 18 Days
Jaya, the core of Mahabharata, is structured in the form of a dialogue between Kuru king Dhritarashtra (born blind) and Sanjaya, his advisor and chariot driver. Sanjaya narrates each incident of the Kurukshetra War, fought in 18 days, as and when it happened.
Reference: https://en.wikipedia.org/wiki/Kurukshetra_War


oak chair remains sticky after using formbys refininisher

Question: I am refinishing an oak chair, after using formby's refinisher, 90% of the chair is smooth and clean, however, the back slats (in this case, round) are still sticky to the touch.  I have cleaned and cleaned and used steel wool and a tacky cloth after, however they remain sticky.  any ideas.  thanks
Answer: Different wood will dry at different rates.   So if you're touching a dry part and concluding "something must be wrong since it's not all dry", just wait.
I would not muss with any painted surface which is still tacky, unless you want the mussing material permanently embedded in the coating.
There are some additives you can add to oil-based coatings to make them dry faster.
It also helps to remove humidity, so if you're in a very muggy area (e.g. Florida or Ohio), consider putting it in a room with a dehumidifier.  Don't blast the dehumidifier straight at it, or you'll stick a bunch of dust to it.
If you want to hasten drying, try putting the item in your car (put down some plastic first) and leave the car out in the sun.  As you know from tragic stories about babies and dogs, car interiors get rather warm in the direct sun. If you don't want it to get to 160F, crack a window or two.  This will make your car smell funny for a day.
Keep in mind also: Curing is not the same thing as drying.  Dry means tack-free.  Cured means the coating has polymerized and reached full strength.  Most paints have a vulnerable time when they are tack-free, but hardly begun their cure.   I once sat in a "tack free" chair only to get up and find my denim pattern imprinted on the "tack free" surface.


How to bypass download manager and download the files from web?

Question: Now a days almost on all websites we see some kind of download managers which we need to download first. when we run that file then it manages the original file download which is a bit annoying for me. Is there anyway to bypass such download managers and download the original file directly in old kind of way?
Comment: Avoid Softonic :) and go for free (in the sense of free speech) or open source software: they always give the binary or the source code, without annoying installers.
Comment: Try to download from softpedia and brothersoft they are good sites. Also there are many sites available to download the software without download the download manager of the sites.
Answer: In general, no. If there really isn't a "manually download" link on the page (frequently there is, it's just obscured/not obvious on many websites that use download managers), then there's probably not an easy way to bypass the manager program.
Sometimes, but not often, using an obscure browser will trigger manual downloads since the manager apps can't get hooks to install. Don't bet on this, though.
Websites that use download managers often use them because advertisements or other spam are distributed with the manager app. The site owners will get money for exposing you to those ads/spam, so it would be against their interests to provide you with an obvious, easy-to-use manual link that bypasses it. This is evil and annoying, but an unfortunate cost of doing business with some sites.
Some sites don't do this: Dell, for example, allows manual download, but also provides a download manager which can come in handy when downloading dozens or hundreds of driver files.
A good rule of thumb is: if there isn't an easy-to-see "manually download" link/button, try to find a different site that provides the file you're after.


Correlating ratio level variables that violate assumptions of all tests I can find.

Question: My survey collected data from 384 respondents, and I have an overall score for each of them on each variable. Therefore, I'm working with 3 composite variables at the scale/ratio level. I want to know what the relationship between these 3 variables is. Unfortunately, my data violates many of the Pearson's and Linear Regression assumptions: non-normal distribution, non-linear or monotonic relationship, outliers. I can't seem to find an appropriate test. Any suggestions? (FYI, not a stats pro so layman's language appreciated).
Answer: Spearman's correlation can be used to correlate your variables. It is invented for situations where the assumptions of Pearson's do not hold.
Comment: Thank you Tim. From what I've read, Spearman's also assume a monotonic relationship, which my variables don't have. The scatterplots are all over the place. Any other suggestions?
Comment: Hi @Mich. Having a scatterplot "all over the place" is not a problem. The requirement for a monotonic relationship that you refer to is probably only that, as the values of one variable increase then, on average, so do the values of the other. Or, as one increases, the other decreases. That you have a lot of noise on your scatterplots means that the correlation will be low, which is separate to the question of the monotonicity of the underlying relationship. If you do not expect a monotonically increasing/decreasing relationship, you should not be computing correlations at all.
Comment: Awesome! Thanks very much. I'll go ahead with the Spearman's then. Much appreciated.


auctex and pdf-tools in 2 separate frames for dual monitor setup

Question: For auctex with pdftools it is convenient for me (eyesight problems) to have the emacs latex frame on my laptop close to my eyes, and the corresponding pdf (in pdftools) on a separate frame on the dual monitor. How can this be implemented? i.e., emacs latex source in one frame and corresponding pdftools pdf in a separate frame. (Typically latex and pdftools exist in the same frame with two different buffers e.g. with C-x 2; but I want two different frames so that I can drag these frames independently to different monitors)
Answer: This is a variation of the question about preview the pdf in a split buffer beside the source.
You can use the following Elisp code in your init file.
If you do not have already two frames. The pdf view will open in a window beside the window with the LaTeX source. Select that window and type C-x 5 2 for make-frame-command. There will be a new frame showing the pdf. You can delete the original window showing the pdf now. If you call TeX-View the window in the other frame is used.
(defun framesMenus-display-buffer-use-some-frame (fun &rest args)
  "Use `display-buffer-use-some-frame' as `display-buffer-overriding-action'.
Then run FUN with ARGS."
  (let ((display-buffer-overriding-action '(display-buffer-use-some-frame)))
    (apply fun args)))

(advice-add 'TeX-pdf-tools-sync-view :around #'framesMenus-display-buffer-use-some-frame)
(advice-add 'pdf-sync-backward-search-mouse :around #'framesMenus-display-buffer-use-some-frame)

Comment: Thanks. Forward  search works fine: latex frame points to new pdf frame.  But  reverse search,   splits the pdf frame into two buffers and shows the latex source in the same frame as the pdf.  More generally: Is it possible to split latex source frame into two buffers and pdf frame into 2 buffers; where top latex buffer talks to top pdf buffer in separate frame, and bottom latex buffer talks to bottom pdf buffer in separate frame. I know you answered related question for 4 buffers in 1 frame; but because of eyesight problems I need  separate frames.
Comment: Also inverse search should work now. The splitting into two windows per buffer is another question. Maybe, putting the LaTeX-buffer of tex document 1 together with the pdf view of tex document 2 into one frame and document 2 together with pdf view of document 1 into another frame works.
Comment: @Vikram Maybe, the setup I described in [my last comment](https://emacs.stackexchange.com/questions/55395/auctex-and-pdf-tools-in-2-separate-frames-for-dual-monitor-setup/55405?noredirect=1#comment86677_55405) is not appropriate for you since the second monitor is further away than your laptop display. ... As I already mentioned. That problem is a separate question.
Comment: Thanks Tobias - it now works perfectly! I'll put the related question (two latex buffers in one frame and two pdf buffers in another frame) as a separate question.


Relationship between KM-estimator and Cox model

Question: What is the relationship between KM-estimator and Cox model? What I am aware is that Cox model allow us to adjust covariates. If I build a Cox model and draw a KM curve (using survdiff function). Would the curve reflect the result of Cox model (covariates adjusted) or the result of KM-estimator (single variate)? In another word, can I using KM curve to show the result of Cox model?
Answer: The Kaplan-Meier curve is the non-parametric maximum likelihood estimate of the survival function. The significance test for differences in survival is the log-rank test. The log-rank test is the score test for the Cox model with the variables adjusted as strata, so they should provide very similar answers. Cox models can fit way more complicated survival data, though, using frailties for correlation, left, right, and interval truncation, time varying covariates, strata and continuous variable adjustment. So the Cox model is more broad and versatile.
You should almost always show the Kaplan Meier curve with any type of survival analysis, even when the graphical display only approximates the inference presented in tables/summaries of Cox model output. It's the same as scatter plot for multivariable linear models: they go hand-in-hand.
Comment: I am not sure if I understand you correctly. Seems like that KM curve shows approximation of Cox model. I am under the impression that we usually present forest plot of Cox model result while KM curve of KM estimator result. Is this correct?
Comment: @unicorn I think you are confusing empirical estimates of overall survival (KM) with a graphical representation of the hazard ratios and their uncertainty (forest plot).
Comment: I read about KM as empirical estimation. But I did not understand why it is 'empirical'. Also, Why do you say forest plot is 'uncertain'? I thought forest plot created by Cox model is the more precise result comparing to KM.
Comment: @unicorn uncertainty is another way of describing standard error. The KM curve has a 1-1 relationship with the empirical distribution function $S_{KM}(t) = 1-\mathbb{F}(t)$. Too advanced to formalize in a comment, but trust me it is so. You should also appeal to the intuitive aspect of it to: there are no predisposing assumptions behind the KM curve, it's just a running fraction of people at risk.


How exactly do I calculate and interpret factors in Fama-French model?

Question: Could anyone explain me how to interpret factors and what kind of regressions I should run?
I have already calculated the factor returns as well as 6 Fama-French portfolio returns, the only problem is I do not know how to properly combine all the information and reach useful results.
Do I run regressions on SMB and HML to find whether those factors explain market movements by looking at R squared and then run regressions on 6 portfolios to see how significant the portfolio returns are?
Comment: If any of the answers were helpful accepting it is appreciated - Thank you
Answer: The clearest hands-on explanation I have seen so far is the following:
Bernstein, W.: Rolling Your Own: Three-Factor Analysis
Everything is explained very clearly and step-by-step with Excel.
Concerning your question: The R-squared tells you how much percent are explained by the factors. The intercept is your alpha, the coefficients of the factors tell you in which direction the portfolio is tilted (e.g. HML for a value fund) and the t- and p-values tell you whether the factors are statistically significant.
As @WillGu correctly mentions you should use the data from the FF website.
Hope this helps to get you started.
Answer: I believe you have every right to "calculate" the FF factor returns, but you might just use the factors returns on their website. As you mentioned, you can regress on these factors and $R^2$ should tell you how much of the variance in your return series can be explained by FF factors.
I'm not quite sure what goal you are trying to achieve, but one use case would be something like "alpha research". If these factors are represented by available products in the market, you might just subtract their contributions from your returns series and focus on the residuals.
On the other hand, running regression on the 6 portfolios (returns also available on their website among others) shows how much of your return variance can be explained by the 6-portfolio returns. The only usefulness of this kind of analysis IMHO is to see what existing portfolio does your return series mostly look like.
Answer: The Fama French SMB and HML portfolios represent the Size premium and the Value premium respectively observed in the equity markets.
Its not clear what your intention is but here's what I would suggest

Take the return series of your portfolio, align it with the factor returns of the SMB and HML portfolios which you can download from Kenneth French's website as pointed by @WillGu
Run a multiple regression of your portfolio returns vs HML and SMB with an intercept.
Observe the coefficients on SMB, HML and also the intercept as well as their t-stats (p-values)
Observe the R-squared
Here is one interpretation

If you observe high R-squared and significant coefficients, this would mean a large percentage of your returns are explained by SMB and HML.
In addition, if you observe a significant and nonzero intercept - it would mean your portfolio returns are also being explained by factors outside of SMB and HML.


Changes in Orbital Parameters Due to Drag

Question: Other than STK, are there any commercially software packages available to model changes in orbital parameters due to increases/decreases in satellite drag. I am trying to figure out if aerodynamic drag can be used in LEO for orbital maneuvering.
Comment: Are you interested in commercial soft only? Doesn't open source count?
Comment: If you manage to use aerodynamic drag for orbital maneuvering in a very low orbit, you have to pay for it by very rapid orbit decay in some weeks or months. A higher orbit with a longer lifetime has much less drag, may be too few drag for maneuvering.
Comment: just fyi for the aerodynamic forces on a spacecraft in LEO, the component along the direction of travel is called "drag" and the components perpendicular to it are called "lift". There is a lot more here about lift and spaceflight: https://space.stackexchange.com/search?q=user%3A12102+aerodynamic+lift
Answer: One of the problem with drag models is that most are not very precise. The few which are precise are usually written in FORTRAN, and lots of tools just interface with the FORTRAN code instead of rewriting and re-validating the algorithm.
The typical high fidelity drag models are the Jacchia Roberts models and the more recent NRLMSISE00 model. The former is only available in FORTRAN to my knowledge. There is however a validated NRLMSISE00 model in Julia: https://github.com/sisl/SatelliteDynamics.jl . Documentation is available here: https://sisl.github.io/SatelliteDynamics.jl/latest/modules/earth_environment/nrlmsise00/#NRLMSISE00-1 .
Answer: I add this here just for completeness: The General Mission Analysis Tool (GMAT) also can model the spacecrat drag. GMAT doesn't belong to commercial software, but it is available.
GMAT has two atmospheric models in its stock distributive: Jacchia Roberts, which can be used for altitudes more than 100 km only, and MSISE90 (for any altitudes).
Copernicus probably also do the similar things, but it seems available for NASA contractors only.
Comment: Let's also note that GMAT is used in spacecraft operations, so it is considered validated software. As for Copernicus, I do not believe it supports drag models: its primary purpose is the design to Earth-Moon trajectories if I recall correctly.
Answer: The main commercial competitor to STK is FreeFlyer.  They're actually having a users conference right now, which you could join at https://ai-solutions.com/ffuc2020/
Another free tool to consider is Orekit, from https://www.orekit.org/
Drag modeling is seriously hampered by the lack of attitude information.  "High-fidelity" only applies to modeling the atmospheric density.  The shape of the satellite is ignored in every implementation I know.  The object is universally treated as a sphere (the "cannonball model").  The farther from spherical a drag-feeling body is, the less well any atmospheric model, no matter how good, will be able to do.  I have used detailed satellite models (how big are the solar panels, what direction do they point, what color are different parts of the surface painted, etc.) to compute solar radiation pressure, but I haven't seen anything like that for drag.  If there is a way to do it, I'd like to use it!


Quantum Mechanics and the Airy Function, the physics of the turning point

Question: I'm working with the Airy function, and the book states at $x=0$ is a turning point, and there are two very different behaviors on either side. In general what a does a turning point mean in differential equations? A point where the highest order derivative in the equation equals zero? The book says this makes sense, oscillatory and decaying on either side of the turning point. But if $E>$ turning point it decays, that's the opposite case of the finite square well right? if $E<$ potential then it decays. What does it physically mean to have a turning point there, and why is it oscillatory when $E$ is greater than the turning point? This is so unintuitive, these potentials confuse me.
Comment: In my experience, "turning point" is the term used for the point where the particle would turn around *classically*. I don't know (I doubt it) if it has become a standard term in the study of differential equations outside of any physical context. Quantum mechanically, the turning point separates "classical-like" behavior (with positive $E$) from "really qm-like" behavior (tunneling with negative $E$).
Answer: Consider first the classical theory. Turning points are these points $x$ where the total energy is completely stored in the potential energy, $E = V(x)$. Hence the kinetic energy is zero at these points. For example consider the potential of the Harmonic Oscillator $V(x) = x^2 / 2$. Then the turning points are $x_t = \pm \sqrt{2 E}$. The pendulum oscillates between $x_{-} = -  \sqrt{2 E}$ and  $x_{+} = -  \sqrt{2 E}$, and hence makes a turn at these maximal points.
Now turn to the quantum mechanic picture, or to be more exact to the semiclassical WKB method. One tries to approximate the quantum mechanic solution by some other functions. In the case of the Harmonic Oscillator these approximating functions are exactly the Airy functions (with some prefactors). So looking at the solution from wikipedia,  one sees that the behavior of the wavefunction changes at the turning points (the potential is drawn in blue, so the turning points are approximately where the wavefunctions intersects the blue graph). For the region between the $x_t$ one has an oscillation whereas for greater $x$ the wavefunction is exponentially damped. This is just as for the Airy function.
http://upload.wikimedia.org/wikipedia/commons/9/9e/HarmOsziFunktionen.png


Type 3 anova for not nomally distributed data

Question: I am running a full factorial anova on my data but when I apply Levene's test and Shapiro test not all of my subsets give positive results. I have already transformed the data with log2 but that doesn't change much about the homogeneity or normality. Someone told me that I might be able to use a type 3 Anova instead but I can't find any specific information about whether you can or cannot use type 3 for not-normally distributed data. Can I use a type 3 anova do I need to do non-parametrical tests for the not normally distributed subsets?
Comment: maybe you could take a look into Box-Cox transformation. Also have you tried to look into other families (binomial, poisson, power, etc)? To make it easier for people to help you you should include an example of your dataset  and the code you tried.
Answer: Using a type-3 ANOVA will not eliminate the problems associated with heteroscedasticity or non-normality. While it may potentially give you greater power to detect the effect you are interested in, this is conditional on meeting the ANOVA assumptions in the first place. In general, the choice of the 'correct' type depends on the hypothesized effect (main, interaction) and your cell sizes and may thus be effectively considered fixed.
It would be helpful to have the following information: a histogram of your distributions, the group variances, the group sizes, and possibly the outcomes of your tests. Even if Levene's test and Shapiro fail, it might not be strictly necessary to switch to a Kruskal-Wallis test.
As for transformations, R's boxcox function allows you to explore a range of values for your transformation parameter.


Can we evaluate the efficiency of Rankyne Cycles by a Diagram T-s?

Question: We can change a standart Rankyne Cycle with reheaters, feedwaters, etc etc. If we look at each diagram T-s, are we able to directly conclude which type of Cycle has a higher efficiency?
Answer: For a continuous cyclic process like this, operating at steady state, the open system version of the first law of thermodynamics tells us that the net heat added Q is equal to the net shaft work Ws.  If the process is operated reversibly, the heat inputs and outputs through the various segments of the cycle are determined by the integrals of TdS, and, of course, the net heat Q is the integral of TdS around the cycle.  So the shaft work is also equal to the integral of TdS around the cycle. Under these circumstances, the T-s diagram can be used to evaluate the cycle efficiency.


3dconnexion mouse locks rotation when in Top view

Question: My Spacemouse locks up in any of the orthogonal views (Top, Left, Right, Front or Back). I have set Auto perspective on (and this works for my other input devices), but not for my 3d mouse. Which settings should I change so that I can rotate the top view to other non-aligned views and/ or rotate (roll) within the top view?
Answer: In such a case it is always difficult to understand how your setup is built and how exactly this behavior is noticeable.
But maybe these screenshots can help you, which show a working setup.

(Sorry for the language settings, unfortunately they can't be changed that easily.)
Comment: What happens if you go to top view? Does that lock your rotation axes as well?
Comment: The only real differences in my setup are that I use NDOF > Orbit for navigation and Turntable for rotation and different sensitivities, the rest is the same. And these other settings lock-up in top view too.
Comment: @Hologram Are you using a "Spacemouse" or "Spacemouse Pro"?
Comment: The Spacemouse Pro wireless
Answer: If I understand correctly, you want to use the Spacemouse T/F/R buttons to switch to one of the orthographic views, but then use the controller to rotate straight back into a perspective view?
Before changing any setting in the 3DConnexion software, try this and see if it does what you want (assuming you have not remapped any of blender's default numpad key assignments):

Switch to an orthographic view like Top/Front/Right using either the T/F/R buttons on the Spacemouse or [Numpad 7/3/1]
Spacemouse control cap will let you pan and zoom but not rotate, i.e. you're locked into that iso view
Press [Numpad 5] which will toggle back to a perspective view
Now the Spacemouse will let you spin/roll/tumble/etc

If that's the behavior you're after, go into 3DConnexion settings and setup a macro named something like "Perspective Toggle" and just assign [Numpad 5] to it. Personally I assigned this macro to the top-left button in the group on the right where the other view buttons are. By default this button is supposed to "Roll CW" but that didn't seem to actually correspond to any actual blender command so I put my Perspective Toggle macro there instead.

Hope this is what you were looking for, enjoy!


Do Saitama and Garou have superhuman hold breathing capabilities, or no need for air at all?

Question: In One Punch Man manga chapter #167

 Saitama and Garou have a fight in Io, the Jupiter satellite, where there is no air

Do Saitama and Garou have superhuman hold breathing capabilities, or no need for air at all?
Comment: Related/possible dupe: [Can Saitama breathe in space?](https://anime.stackexchange.com/q/29216/2516)
Answer: Implicitly: Superhuman hold breath for Saitama, at least; put possibly a greater power.
Why:

 In Chapter 168, after a fairly long (by Saitama standards) battle on Io, Saitama eclipses Garou entirely and emits a Serious Sneeze. A sneeze strong enough to travel all the way to Jupiter and blast away its atmosphere enough to expose its core (and wreck most of Io and send both of them flying away, seemingly in excess of escape velocity of Io and Jupiter). This would require a massive amount of air, which Saitama must have simply been holding onto this entire time. This even despite no apparent effort being made to actually hold his breath or to in any way stop air from escaping his body.

The ridiculous part:

Indeed, without attempting to actually calculate it, I would hazard the guess that the effects on Jupiter would require well in excess of the entire atmosphere of Earth to have been ejected during the sneeze. If so, perhaps the answer isn't Super Hold Breath, but rather Super Create Air: he produces whatever air he needs to do what he wants to do it, or an effect equivalent to it.  So he wants to talk, so he has enough to talk; he wants to sneeze or fart prodigious volumes and velocities, and he produces enough to do that.

For Garou:

 In his cosmic form he is said to have connected to the means of producing all forms of energy in the cosmos. So he could create breathable air for himself on the fly through, say, nucleosynthesis (Big Bang style if need be: create tons of energy, condense it into air molecules). He could also simply create all the side effects of having adequate air on the fly: he can create the soundwaves to talk, he can just give his cells the energy needed without relying on chemical reactions, stimulate his nervous system to send the "yep, we're breathing just fine" signal, etc.

Combined conclusion for Saitama:

 Combined with Saitama's ability to grab and manipulate dimensional portals at will like some sort of Looney Tunes character, as well as his ability to evidently "mimic/copy" Garou's power so well he can achieve a time travel ability Garou could not, which itself explicitly involves control at an atomic scale at least, I would conclude that even "Super Create Air" is underselling what Saitama is doing.  He seems to instead have a "Do whatever I want" reality-bending style of power. He's limited (upwards at least; maybe there's a floor on how weak he can be) only by his conception of what he could do if he wanted to: he doesn't fly because he doesn't think that's possible, but he can fart with impossible control to achieve space travel along precise paths; he doesn't think he can time travel until Garou insists he can by just mimicing him (which he says is actually Saitama using God's power without being connected to or corrupted by God). He's too focused on dealing with Garou after Genos's death to realize he should have problems breathing (or even being able to talk at a distance), so he has no such problems as he defaults to "duh, of course I can breathe, doesn't even require me to think about it to do that", etc.
Comment: I'm not sure if the sneeze would require a lot of air. Because from Physics momentum is p = m v , which means an incredible high speed would add a lot of momentum to any mass, no matter how tiny the mass (or sneeze) is
Comment: @Pablo There's a massive difference in scale, for one. Jupiter is radically larger than Saitama, and its atmosphere much more dense than Earth's. At a normal lungful of air you'd probably be looking at (hyper) relativistic velocities, which would have produced nuclear reactions and fusion events all along the pathway which aren't evident. And the propagation speed of the event seems unlikely to be consistent with a small number of super high velocity particles initially impacting and most of the observed effect just being secondary and beyond collisions. But, again, haven't calculated.


What is the difference between Common Goods and Common Pool Resources?

Question: All this time I was thinking that common-pool resources are common goods, until I read this excerpt from a book.
Comment: Do "common goods", "collective goods" and "public goods" to refer to the same thing?
Comment: The term used in your quote is "collective goods", not "common goods".
Answer: Common pool resources can be depleted by overuse.
For example, an area of communal grazing land would be a common pool resource because grazing too many animals decreases the amount of grass available to each animal.
Wikipedia is a common good but are not a common pool resource - reading a lot of articles on Wikipedia does not reduce the number of articles available for everyone else to read.
Comment: Can Wikipedia be considered as a Common Good?

According to theory I have come across, for something to be a public good it has to be non-excludable and non-rival.
For example, sunshine. Can you exclude people from enjoying sunshine? Nope. No one can be excluded.
Does sunshine have any rival, that if I am using it, someone else cannot use it? Nope. Anyone can use it.

So, sunshine is non-rival and non-excludable. So, it is a public good.

Same goes for Wikipedia as well, that no one can be excluded from using it, and if I use Wikipedia does not mean other person cannot use it.
Answer: A useful reference is the matrix proposed by Elinor Ostrom:

Source: Hess & Ostrom (2007)
Common-pool resources (= Common goods, Wikipedia):
using them impacts others + exclusion is difficult (e.g. the climate)
Public goods (= Collective goods, Source):
using them does not impact others + exclusion is difficult (e.g. knowledge)
i.e. what Taylor says is that privatising the atmosphere would not resolve the collective action problem; although it would make sense given that its use is subtractable (= rivalrous) it cannot be done because exclusion is difficult.


Re: Touching your toes (not mentioned in 30)

Question: My mother could touch the heels of both hands on the floor up to the age of 89. She had short legs and a long torso. Is it likely that someone who cannot reach his toes has a short torso and long legs, compared with the norm?
Answer: Being able to touch the toes depends mainly on two things:

hamstring flexibility
body proportions (relative length of legs, torso, and arms)

It is not possible to change body proportions, so, to reach the toes, someone with longer legs and shorter torso/arms will need to have more flexibility in the hamstrings. It is possible for anyone to reach that level of flexibility. See:

(source)
How is hamstring flexibility measured?
In the hamstring flexibility test (also called straight leg raising test, or SLR test), the maximal angle of flexion of the straight leg is measured in a lying down position:

The usual classification is:

inflexible for below 65 degrees
normal for around 80 degrees
above average flexibility for 105 degrees or more

What about age?
Muscles tend to become shorter with age, however, maintaining flexibility is quite easy with a little work. Flexibility is much easier to maintain than to acquire. An old person, who has acquired flexibility when he/she was young, will need to spend a lot less time maintaining it, compared to a younger, but inflexible person trying to become flexible. That said, flexibility can be improved in any age, I have seen people in their 30s, 40s, 50s gain much flexibility.
So, can I blame factors that are out of my control, for my inability to reach my toes?
No. The reason is lack of training.
Comment: I've edited my post to try to answer the question better.
Comment: While this is a great post, it doesn't answer the OP's question at all.
Answer: It's possible, but I wouldn't call it "likely" in the sense that "this is the most probable reason". The most likely reason is simply a lack of flexibility.
If one, over a longer period of time, works on their flexibility, most people (barring certain "disabilities") will be able to reach their toes, or even palms, the floor.


Dectecting stamp (seals) imprints on digital image with SIFT

Question: I am working on an application that should determine if input image contain a stamp imprint and return its location. For RGB images I am using color segmentation and doing verification (with various shape factors), for grayscale image I thought that SIFT + verification would do the job, but using SIFT would only find those stamps(on input image) that I got in my database.
In ideal case it works really well, as shown on image bellow.
Fig. 1.
https://i.stack.imgur.com/JHkUl.png
The problem occurs when input image contains a stamp that does not exist in database. First thing I did was checking if there would be any matching key points if I compare a similar stamp to the one on input image. In most cases there is no single matching key point and if there is some they rather refer to other parts of input image than a stamp, as shown in Fig. 2.:
Fig. 2.
https://i.stack.imgur.com/coA4l.png
I also tried to find a match between input and circle images as the stamps are circular, but circle image has very few key points, if any.
So I wonder if there is any different approach that will make SIFT a bit more useful in this exact case? I though about creating a matrix with all descriptors and key-points from my database and then looking for nearest euclidean distance between input image and matrix, but it probably wont work as there is a lot of matching key-points(unwanted) across the database (see Fig. 2.).
I'm working with Matlab and tried both VLFeat and D. Lowe SIFT implementations.
Edit:
So I found a way to force SIFT to compute descriptors for user defined points on an image. My test image contained a circle, then the descriptors were computed and matched against input images, including the one under Fig 1 and 2. This process was repeated for scales from 0 to 10. Unfortunately it didn't help too.
Comment: If all your stamps are round, I would actually start with a Hough transform to find circles. Then you can take just the candidate areas and compare them to your actual stamp images. I imagine you might be able to train an SVM or something to deal with it.
Answer: This is only a first hint and not a full answer to the SIFT questions.
My impression is that detecting a circle by matching it against an image of a circle via SIFT is not the best approach, especially if the circle you want to detect has some unknown texture inside.
The textbook algorithm for circle detection would be Hough transform, which is mostly used for line detection but does work for any kind of shape which can be described by a low number of parameters (colleagues tell me things get nasty above 3, but a circle just has X,Y and r). There are several implementations in file exchange, the link is just to one example. Hough circle detection requires you to put an upper bound on the radii you want to detect, but this seems ok for your application.
From the examples you provided it looks like you should get quite far if you can detect circles reliably.
Comment: Thanks for your answer. I know about Hough transform, but the original idea was to use SIFT as it is scale-invariant in contrast to Hough transform, which make it resource hungry. However if I fail to come up with any idea I am going to use Hough transform, I would also give Harris corner detector a go.

Another disadvantage of Hough transform is that I am detecting also square, rectangle, triangle, oval stamps. There is also a group of irregularly shaped stamps so there is no way they could be described.
Comment: I get your point - you want to know whether SIFT can do the job. From my experience with SIFT I think it probably cannot, at least not the circle or shape detection part. This is simply not what SIFT is for: It aggregates local properties of texture (in a way which is invariant under certain transformations), but it is unaware of geometric entities like circles etc. If you want to detect the unknown patterns with SIFT I thinks you have to use a full machine learning approach, feeding the SIFT descriptors, for example, into an SVM which you train on your known patterns.
Answer: Actually I do not think SIFT will be solving this problem. I've been playing around with SIFT for quite some time and my conclusion is that it's really great for identifying identical patterns but not for similar patterns.
Just have a look at the construction of the SIFT feature vector: The descriptor is composed of several histograms of gradients(!). If you have patterns in the database that have very similar blob like structures in the stamps, then you might have a chance. But if this does not hold, then I guess you will not be very lucky.
From my point of view you have kind of solved the problem of finding indentical objects (stamps) and now extend to finding similar objects. This sounds like the same but in my past research I found these problems just related but not too identical.
Do you have any runtime constraints in your application? There might be other approaches but in this case, more input about possible constraints might be useful.

Update regarding constraints:
So your next task might be to detect the unknown stamps, right?
This sounds like a classification task.
In your case I would first try to find a descriptor/representation (or SVM) that classifies images into stamp/no-stamp. In order to evaluate this, set up a data base with ground truth and a reasonable amount of "unknown" stamps and other images like random snapshots from the letters, NOT containing stamps. This will be your test set.
Then try some descriptors/representations to caluclate the distance/similarity between your images to classify your test set into the classes STAMP / NO-STAMP. When you have found a descriptor/distance measure (or SVM) that performs well in classifying, then you could perform a sliding window approach on a letter to find a stamp. The sliding window approach is certainly not a very fast method, but a very easy one.
At least when you have reached this point, you can tune the detection - for example based on interesting point detectors.. but one step after the other...
Comment: You're right about SIFT, it is not applicable in my work. I tried to extort key-points for which SIFT calculates features vector, and put them on edges of stamps, but SITF is texture-only sensitive and it won't work like this. That's why I gave up on it and used circular Hough, Hough for lines and other approach, suggested [here](http://stackoverflow.com/questions/12158396/how-to-check-if-four-points-form-a-rectangle).
Comment: To answer your question, I do not have any runtime constranst, as it is part of my Bsc thesis, but on other hand I can't go extreme. If you have any suggestion please share, it would be much appreciated.


rails assets image not find after enalble apache x-sendfile

Question: I've a problem in my website. It's made using:

ruby 1.9.3
rails 3.2.9
and it's hosted by apache 2 server.

The server worked fine, but yesterday i apport a change in my code.
i needed to add a big files downloader and for this i used the apache module: x-sendfile.
when i configured it, the download operation had no problem. But when this module is enabled the site's images have not to show
I see that the problem start when i enable the module in my config/enviorment/production.rb file by adding the row:
config.action_dispatch.x_sendfile_header = "X-Sendfile"

The probem is that rails command image_tag("it.png") search file in /assets/it.png without find it.
I think that it's a problem with assets pipeline configuration.
This is my config/enviorments/production.rb file:
IdePro::Application.configure do
    # Settings specified here will take precedence over those in config/application.rb

    # Code is not reloaded between requests
    config.cache_classes = false

    # Full error reports are disabled and caching is turned on
    config.consider_all_requests_local = true
    config.action_controller.perform_caching = false

    # Disable Rails's static asset server (Apache or nginx will already do this)
    config.serve_static_assets = false

    # Compress JavaScripts and CSS
    config.assets.compress = true

    # Don't fallback to assets pipeline if a precompiled asset is missed
    config.assets.compile = false

    #config.assets.precompile += ['logo.png']

    # Generate digests for assets URLs
    config.assets.digest = true

    # Defaults to Rails.root.join("public/assets")
    # config.assets.manifest = YOUR_PATH

    # Specifies the header that your server uses for sending files
    config.action_dispatch.x_sendfile_header = "X-Sendfile" # for apache
    # config.action_dispatch.x_sendfile_header = 'X-Accel-Redirect' # for nginx

    # Force all access to the app over SSL, use Strict-Transport-Security, and use secure    cookies.
    # config.force_ssl = true

    # See everything in the log (default is :info)
    # config.log_level = :debug

    # Use a different logger for distributed setups
    # config.logger = SyslogLogger.new

    # Use a different cache store in production
    # config.cache_store = :mem_cache_store

    # Enable serving of images, stylesheets, and JavaScripts from an asset server
    # config.action_controller.asset_host = "http://assets.example.com"

    # Precompile additional assets (application.js, application.css, and all non-JS/CSS are already added)
    # config.assets.precompile += %w( search.js )

    # Disable delivery errors, bad email addresses will be ignored
    # config.action_mailer.raise_delivery_errors = false

    # Enable threaded mode
    # config.threadsafe!

    # Enable locale fallbacks for I18n (makes lookups for any locale fall back to
    # the I18n.default_locale when a translation can not be found)
    config.i18n.fallbacks = true

    # Send deprecation notices to registered listeners
    config.active_support.deprecation = :notify
end

Answer: Try using:
image_tag(image_path('it.png'))


Icons (or term) to show breakfast, lunch, dinner and snack(each)?

Question: I have a page where the user selects breakfast, lunch, snack or dinner. I have the words below each button. I cannot seem to figure out what icon I can use to differentiate each. So that the user says "Oh there's breakfast."  I had a fork and knife icon for dinner. I used a leaf for a snack. Then I became absolutely stumped.
Comment: The difference between those 4 items isn't the type of food one eats per-se, but the time of day. As such, focus on time-of-day iconography.
Comment: Hi @Johnston.  Unfortunately "What Icon Should I Use?" is not a question we can really help with, per the [this Help Center](http://ux.stackexchange.com/help/on-topic) post.  You can read more about [the rationale](http://meta.ux.stackexchange.com/questions/629/is-it-time-to-put-an-end-to-icon-for-x-questions) and tips on [generating useful icons](http://ux.stackexchange.com/questions/14571/how-do-you-create-or-select-an-icon-for-a-feature).
Answer: I would try the noun project for these icons. You can either take inspiration from what you find there or use what you find there as long as you purchase it or give the artist attribution.
These are broad concepts that call up different imagery for different people depending on their cultural background. Who is your audience? Is this also for the daycare project (but on the input side of things... lol)?
http://thenounproject.com/search/?q=breakfast
http://thenounproject.com/search/?q=lunch
http://thenounproject.com/search/?q=snack
http://thenounproject.com/search/?q=dinner
Comment: This is for the admin/teacher input side of things. It is the child who is eating the breakfast. This is a great site.
Answer: I would use the following type of icons:

For breakfast an icon of egg.

For lunch an icon that has a dish.

For dinner an icon that has a covered dish.

For snack an icon that has a cupcake or pop-corn.
Comment: Although neat icons, they lack specificity and are mostly interchangeable.  Breakfast: I don't eat hard boiled eggs, nor do I play with silly putty anymore.  Lunch: I love spaghetti but associate it with dinner; same goes for any hot plate meal.  Dinner: Catered meals are not not in my budget, nor has anyone every presented me my meal covered.  Snack: I eat muffins for breakfast.  An icon for icons sake is not a good idea.  Breakfast/Lunch/Dinner is arguably too subjective to separate with different icons.
Comment: I agree with @EvilClosetMonkey, take the text you have already to the next level(?) with a beautiful and easy readable font instead. Always works :)
Comment: Since the asker did not say if this is to be _global_ iconography, I see no reason why the icons suggested by @pixelfairy should not be fine. We do not know the scope; if this is supposed to span the entire globe and millions of people, every conceivable culture, then yes, maybe icons would be a problem. But everything has a context, and if the user need a tiny-weeny-bit of learning to get it, that is often fine. The combination of icon and text would enrich, not actually confuse. We must allow users to "learn" a little sometimes. Very, very few things are truly intuitive the world over.
Answer: I agree with the comment by @DA01, that the distinguishing factor between meals isn't what you eat (which can vary from family to family as well as from culture to culture) but when you eat it.  Except for snacks, for which the distinction is how much you eat!
Furthermore, if these icons are part of a large check sheet with many details about the daycare kids' daily lives, you might want a common theme that connects all the meal/food icons at a glance.
These are two possibilities I came up with:

There are limitations to both.
The problem with the analog clock faces is that a lot of people aren't comfortable reading analog clocks at a glance anymore, and that could include your daycare workers.  If snacks are at a set time mid-afternoon, you could add a 3-o'clock face to the snack plate (and make dinner more distinctly 6-o'clock), but I think just having the small plate also gets the idea across.
The problem with the initials is that it is language-dependent, so not ideal if the reason you're using icons is because it's a multi-lingual environment.  Also, that "S" could mean supper as well as snack -- you should probably just skip the "S" on the snack icon and let the small plate size speak for itself.
But my main suggestion is (a) come up with a common icon that means "meal", and then (b) add details that distinguish which meal.


who is responsible as international court to solve economic conflicts between countries and is it obligatory?

Question: you know turkey was one of the 7members of F-35 joint strike fighter program..its engine is being manufactured in turkey.turkish government made all legal obligations to program and paid 35 billion dollars to budget pool so far but american congress decided to end delivery of 200fighters to turkey illegally by trump's decision last week..
so i heard a news on cnn turk this evening that turkey minister of defence is going to moscow to negotiate agreed terms to buy 300 SU-57 stealth fighter from sukoi instead next month..i think this will be important step of turkey's way to waited exit from NATO after S400 agreement of last year..it is called 'bricst-it" in turkey at the moment..it is possible to join to BRICS instead of NATO&EU for turkey..but in continue of news,there will be a government decision of turkey to prosecute united states government worth 1,8 trillion dollars sum plus with all turkey's army lost from F-35 program and legal compensations and interest rate of 20 years..ok here is my question..which international court may look at this case and is decision obligatory?
Comment: I'm voting to close this question as off-topic because it is about international law, not economics.
Answer: As far as I am aware, there is no "general" international court for economic affairs.
The ICJ (Interntaional Court of Justice) is the judicial organ of the UN, and it in fact decided few cases with economic background, but usually in the context of other questions of international law.
The closest to what you are looking for is probably WTO dispute settlement system, which is described here: https://en.wikipedia.org/wiki/Dispute_settlement_in_the_WTO
In theory, it is for WTO members only, but in practice, 96 % of global trade is covered under WTO.
Other possible court is the International Court of Arbitration: https://en.wikipedia.org/wiki/International_Court_of_Arbitration
It has no clearly defined jurisdiction, instead, the parties must agree to bring the case to it, but it is becoming increasingly popular.
Last, but not least, an ad hoc panel can be established specially for given dispute.


Step by Step guide to install aircrack-ng suite on ubuntu 12.04 LTS

Question: I tried soo many guides and soo many things i browsed like the whole world wide web and I could not install aircrack-ng suite.
Any help would be appreciated :)
Thank you all,
Best regards.
Comment: What steps have you taken to install it, errors encountered?
Comment: I understand that this tool can crack WiFi passwords, but it can also be used for pen testing your own network (says `hakermania`), so, this is a legitimate question. Downvoters... please!
Comment: Also, this guide had worked for me: http://www.riyazwalikar.com/2010/12/installing-aircrack-ng-on-ubuntu-1204.html
Answer: I don't know what steps you have taken, but aircrack-ng is in the "universe" repositories.
All you need to do is open up a terminal, and type in the following:
sudo apt-get install aircrack-ng
This will install the whole suite, including airmon, airodump, and aireplay.
Make sure that you have the universe repository enabled. To do that, search and open the "Software Sources" from the dash, and make sure that the universe repository is checked (the highlighted one below).

If all of this still does not work, follow the steps listed in this answer here.
Comment: sudo apt-get install aircrack-ng
Answer: I would recommend you take a look at Backtrack Linux. Its a distribution for penetration testing with all the tools ready to use. Saved me alot of time during a class last semester.