Is 'one' a pronoun referring to 'blue' in the phrase "blue, which is one of my favorite colors"?

Question: In the sentence:
"My car has the color blue, which is one of my favorite colors,"
Does 'one' act as a pronoun of 'blue' (is referring towards blue)?
Answer: The authorities seem to disagree on what part of speech one is in one of my favorite colors.
Merriam-Webster dictionary has the following example sentence under the pronoun definition of one:

I met one of your friends.

This is essentially the same usage as in "one of my favorite colors."
On the other hand, Oxford Dictionaries Online has the following sentence under the cardinal number definition of one:

Electronics is one of his hobbies.

This, again, is essentially the same usage.
Answer: I would say one, regardless of how you classify its part of speech (Peter Shor's answer shows that people may vary on this), is certainly not a pronoun referring towards blue in the sentence "My car has the color blue, which is one of my favorite colors."
The pronoun one is an indefinite pronoun, and as far as I know indefinite pronouns do not have antecedents (or at least, they don't have to). This is supported by the "Write Content Solutions" "Writing Guide" to Indefinite Pronouns, which says that "Indefinite pronouns do not refer back to a particular person, subject or object," although I have no idea if this is a reliable source for information about grammar.
I agree that in sentences such as "Those are nice bikes. I might just have to buy one" the pronoun one does actually seem to have an antecedent. So quite likely, the Write Content Solutions guide is incomplete. Regardless, I think one is used differently in that sentence from how it's used in the original sentence. In "Those are nice bikes. I might just have to buy one," it seems possible to interpret one as an elided or shortened form of "one of them," where "them" refers to the bikes. This is not possible in the sentence ""My car has the color blue, which is one of my favorite colors." Instead, the pronoun one seems here to refer forwards to the noun phrase "my favorite colors."
Consider: if you say "Alice is somebody you don't want to cross," "somebody" is certainly a pronoun, but we don't normally say that it refers back to "Alice." Rather, it's part of the predicate, which is linked to "Alice" by the copula "is." We can use regular nouns in sentences of the exact same structure; for example, "Alice is a person you don't want to cross" or "My car has the color blue, which is a color I like a lot." In these sentences, I wouldn't say that "Alice" is the antecedent of "a person," or that "blue" is the antecedent of "a color." So in the equivalent sentences with pronouns, I don't think the pronouns should be considered to refer back to these noun phrases either.
I think another good example you gave in the comments is " "I like my new shirt. Sadly though, it has one of the worst fabrics." Here, you see that when you use a transitive verb rather than a copula, it makes it very clear that one is not referring back to any previously-mentioned noun in sentences like these. If one referred back to "my new shirt," I'd expect the sentence to mean something like "Sadly though, [my new shirt] has [a new shirt] of the worst fabrics." That just does not make sense. "One of the fabrics" is actually a new noun phrase that doesn't refer back to anything previously mentioned.
Answer: No, one is not a pronoun for blue.
In your case, one is used to denote a particular color out of a number of colors, my favorite colors.
Comment: @Alex, in that case, 'one' is used to mean a particular bike, of a number of bikes. To answer your second question, no. 'one' cannot be substituted with the numerical '1'.
Comment: It's not clear what "acting as a pronoun for" means, but *one* in the OP is a pronoun with antecedent *blue*. *One* in this usage may refer to any kind of antecedent, not just persons. Please consider revising your answer.
Answer: Definitely 'one' doesn't act as a pronoun here. The word which acts as a relative pronoun, the definition of which, I have taken from grammar.yourdictionary.com goes as follows:
A relative pronoun is used to connect a clause or phrase to a noun or pronoun. You see them used everyday with the most common relative pronouns being: who, whom, which, whoever, whomever, whichever, and that.
Here is a full list of relative pronouns:
that, when, which, whichever, whichsoever, who, whoever, whosoever, whom, whomever, whomsoever whose, whosesoever whatever, whatsoever
According to learnenglish.britishcouncil.org,
We use who and whom for people, and which for things.
Or we can use that for people or things.
We use relative pronouns:
• after a noun, to make it clear which person or thing we are talking about:
We had fish and chips, which is my favourite meal.
But no where there is a mention of relative pronoun being used to refer a color.
Whereas "one" is a pronoun generally refers to a person.
Google defines pronoun 'one' as follows:
pronoun: one
1.referring to a person or thing previously mentioned or easily identified.
"her mood changed from one of moroseness to one of joy"
2.a person of a specified kind.
"you're the one who ruined her life"
a person who is remarkable in some way.
"you never saw such a one for figures"
3.used to refer to the speaker, or any person, as representing people in general.
"one must admire him for his willingness"
I hope this clears things.
Comment: *One* is a pronoun here. Its antecedent is *blue*. In fact, the OP's use matches the first definition you give.  The discussion of relative pronouns answers a question not asked. Please consider revising your answer.
Comment: Of course you can use a relative pronoun to refer to a color. *"He painted the house blue, which is my least favorite color."*
Comment: @Alex: that's a great example, I think! If you think about that last sentence, you see that there is no preceding noun phrase that would make sense as an antecedent for "one." It has to refer forwards to the noun phrase "the worst fabrics."


Getting remaining licenses of customer portal using apex

Question: When a new portal user is created, can we check the number of used and total portal licenses?
Comment: I reckon [SELECT Count(Id) FROM User Where IsActive= true and isportalenabled = true] gives you the total portal licenses in use. You could subtract this from total num to give available
Comment: @techtrekker Can we also get total licenses assigned to an org?
Comment: I couldn't find anything just yet, however this is unlikely to be a dynamically changing value, so is It perhaps a candidate for a Custom Setting ?
Answer: THe only way I've been able to achieve this kind of functionality in apex is via screen scraping. Create a pagereference to the company information page, execute the getcontent method to retrieve the raw HTML and then find the table row(s) containing the portal license information and extract the relevant elements.  Its fragile, as there's no guarantee that the format of this page will remain the same (though it has for the last couple of years I've been using this technique) and you also can't execute the getContent from a trigger or scheduled apex, so I've tied it to a visualforce page embedded into a dashboard.
You can access the page via the organization id, so the code to get the content is:
Organization orgDetails =[select Id from Organization
                      limit 1];
Id orgId = orgDetails.Id;
PageReference pr=new PageReference('/'+orgId);
String rawData=pr.getContent().toString();

and then you can locate a particular element using code similar to the following, which extracts the percentage of data space currently used::
Integer pos=rawData.indexOf('Used Data Space');
String result;
if (-1!=pos)
{
   pos=rawData.indexOf('', pos+3);
      if (-1!=pos)
      {
         Integer endPos=rawData.indexOf('%)', pos);
         result=rawData.substring(pos+1, endPos+2);
      }
   }
}

Answer: The technique above worked great for me.  I used it in a Schedulable interface as triggers can't employ the getContent method.  We just run this nightly.  Below is the code I used to implement in our Org:
global class LicenseAvail implements Schedulable {

public String result;
public String orgName;
public String orgCountry;

global void execute(SchedulableContext ctx){

 //Get Organization to get content of company info details
         Organization orgDetails =[ select Id, Name, Country from Organization limit 1];
            Id orgId = orgDetails.Id;
            orgName = orgDetails.Name;
            orgCountry = orgDetails.Country;

        PageReference pr=new PageReference('/'+orgId);
        //called screenscraping: get the data from the page
        String rawData=pr.getContent().toString();

    //locate a particular element within the raw data
    //the info after this line contains the active license count
    String licRow = '>Salesforce	Active	';
    Integer licLen = licRow.length();
    System.debug('******************** licLen: ' + licLen);
    Integer pos=rawData.indexOf(licRow);

if (-1!=pos)
{
         Integer licStart = pos + licLen;
         result=rawData.substring(licStart, licStart+3);
         System.debug('***************** SubString: ' + result);
  }

//get used licenses and determine if count of available is 5 or less

Decimal lic = decimal.valueOf(result);

integer u = [select count() from user where profile.UserLicense.Name = 'salesforce' and isactive = true];

 Decimal userCount = decimal.valueOf(u);

Integer totalUnused = (lic.intValue() - userCount.intValue());
System.debug('************ Licenses???? ***************** ' + String.valueOf(totalUnused));
    if(totalUnused <= 5) {

   System.debug('Sending Email...');
   Messaging.SingleEmailMessage mail = new Messaging.SingleEmailMessage();
   String[] toAdd = new String[]{'firstname.lastname@example.com'};
   mail.setToAddresses(toAdd);
   mail.setReplyTo('email@example.com');
   mail.setSenderDisplayName('Salesforce License Notification');
   mail.setSubject(orgName + ' License Count: ' + String.valueOf(totalUnused));
   mail.setBccSender(false);
   mail.setUseSignature(false);
   mail.setPlainTextBody('License Count: ' + String.valueOf(totalUnused));
   mail.setHtmlBody('License Availability Alert:
' + orgName + ', '+ orgCountry + '
' + 'License Count: ' + String.valueOf(totalUnused));
   List<Messaging.SendEmailResult> results = Messaging.sendEmail(new Messaging.Email[] { mail });
   System.debug('****************** Email Sent: '+results.get(0).isSuccess() );
}

}
}

Answer: There are UsedLicenses / TotalLicenses fields from UserLicense object available only through API call and only available for organization subscribed for related Pilot Program.
If your question relates to usage of UsedLicenses / TotalLicenses fields, you may vote up for this idea https://success.salesforce.com/ideaView?id=08730000000cJTEAA2 and also you may be interested in a managed beta package I created recently which may serve as workaround for this. It screenscrapes company profile page and gets number of total license.
This package includes a User_License_Extended__c custom object which contains Total License number and Used Licenses number ( and some more fields ), these numbers are updated whenever a user is activated or deactivated or user profile is changed assuming package is properly set up with necessary data
Install link for production-like org https://login.salesforce.com/packaging/installPackage.apexp?p0=04t580000001ENa
More details and release notes https://patlatus.wordpress.com/2016/03/07/salesforce-uletas-beta-1-0-release-notes/
Just noticed Bob was giving more advanced approach than I had implemented, using
> PageReference pr=new PageReference('/'+orgId); String
> rawData=pr.getContent().toString();

instead of doing callout - I should try that as well and rewrite my package - didn't know that pr.getContent() may be used for screen scraping
Comment: Guys, i have a requirement for finding out the Total licenses of SF for OTHER orgs which means i would have to screen scrape other orgs. Is this possible?              How can I use the session details to access the /OrgId page of another org? Any ideas highly appreciated.
Comment: @ShaliniMendu Actually my original version of the package already does that: you can screen scrape OTHER orgs Total Licenses, but the threshold email part will not be working as expected


My minecraft world spawn keeps setting underground?

Question: I have a Java server set up through Aternos to play with friends, spawn used to be in an empty field area in the middle of the map and I have recently built a building near by to move spawn to. However, when I tried to set spawn there and test it, it tps me and others to the large cavern 70 blocks underneath the spawn building. I have tried the /setworldspawn with nothing added and with my exact coords, and I have tried /gamerule spawnradius 2 but nothing is working, I will try any and all suggestions people have, thank you!
Comment: It would be useful if you'd include which command you've used.
Comment: ... and what plugins (if any)
Answer: You likely have something like EssentialsEX, Nucleus or Essentials overriding default Vanilla spawning behaviour.
Try /setworldspawn (Essentials), /minecraft:setworldspawn (Vanilla), or /setspawn (Essentials, also).
It is possible you have /spawnpoint yourself. In that case, you may need to use /spawnpoint @a clear (older versions of Minecraft/Essentials) or /clearspawnpoint//minecraft:clearspawnpoint (Minecraft).


Selective deleting of messages from POP3 account via Gmail (or anything else)?

Question: I'm importing emails into Gmail via POP3. Is there a way to delete from the server messages with a certain keyword in the subject and leave everything else on the server? If not Gmail than is there any other way of doing this? It is not possible to create filters on the original server or to add any scripts / cron jobs... Thanks!
Answer: Just found that I have IMAP access too, so I installed Thunderbird and was able to selectively and permanently delete the messages from the server. Not sure if it is possible with POP3...


Why isn't the Reviewer badge a requirement for moderator candidacy?

Question: The moderator's daily job is mostly similar to the /review for which one could get the silver Reviewer badge after some good effort. Why isn't this one of the criteria for a moderator candidate? It's even not mentioned in the list of noteworthy badges at elections.se. The badge is IMO relatively easy to earn and users with the badge show off that they are familiar with the boring day-in, day-out job of a moderator.
Comment: +1 | As far as noteworthy badges, I think this would be more noteworthy than Outspoken and Pundit. Also, why isn't Marshal in there?
Comment: I was going to say it's one of those badges that everybody except the moderators gets, but it seems most of the other mods do have it.
Comment: @mmyers: yes, it's also much similar their job. Do note that /review and the badge is relatively new, they are introduced around the time of the last elections (Nov 2011). So that wasn't applicable during the previous elections and it must tell something about the current users with the badge, how small it also is. We ultimately need "only" 3 new moderators.
Comment: You can change badges that you think are noteworthy on the elections site and add any that you want (even supporter :L).  I agree that reviewer should be included by default though xD
Comment: Why don't we require candidates to have Copy Editor to show that they've spent a lot of time actually editing and salvaging posts, and Marshal to show they can pick problem posts? The noteworthy list is simply that, not everything on it is mandatory for the election.
Comment: @slugster: There are already the Strunk&White and Deputy badges for that which are just silvers. If Reviewer were an gold (and is theoretically thus much harder to obtain), I would probably not have asked this question.
Answer: I would imagine that it's because only 208 users on Stack Overflow would qualify.
That's a fairly small cross-section of the Stack Overflow User Community.  I believe that we're looking for a bit more diversity and representation of the community than that.  We want to draw from a larger pool.
The sorting-out process doesn't end when a moderator gets elected.  I've only been a mod for a short while, and I've seen what I thought to be highly qualified individuals wash out, simply because... well, I don't really know why.   Conversely, I've seen people get elected who made me go o_O, but who turned out to be exceptional moderators.
Consequently, once a user has demonstrated willingness, good judgement and an enthusiasm for sweeping the floors, I'd be more apt to endorse them than someone who simply spent a month earning a silver badge.
Comment: What @Chichiray said, if you want good sweepers up, you need to pick from the existing sweepers up. If there aren't that many sweepers up, this might explain why finding (and keeping) good moderators is so hard...
Comment: Well, new moderators are of course enthusiast about the shiny new tools and status which motivates them to work hard on moderation. But once those are not shiny anymore after some months, the effort of certain users would also fall back that hard. I'd like to filter out this kind of users before I cast my vote. I think having the Reviewer badge is very close to this. After all, wouldn't it be a good idea to see the /review stats for each nominatee? So that we can for instance see if one didn't immediately stop after ~1000 reviews or so.
Answer: I don't think this should be a requirement.   However including the review stats on the voting page, so the voters can decide would be good.


What is the difference in plants rated to 1 zone warmer than where they grow?

Question: I keep hearing about things I want to grow being cold hardy to zone 5, but I live in zone 4, will I still be able to grow those plants?
Comment: Up to you if you want to try.
Comment: Depending on the specific weather, you might get away with it for a few years, and then have it winter-killed when the temperature actually gets down to the cold that defines your zone (which you might not get some years, or even several years in a row). Far better to grow 3 & 4 stuff than 5, in a 4 zone, if you want it to survive. You can also try growing it in a high tunnel or other somewhat protected microclimate.
Answer: Sometimes you can. The winter hardiness zones is an approximation and meant to guide you in which plants to select, however it's broad sweeping. Each area will have microoclimates that are +/- 1 or two full zones depending on circumstances.
A south facing slope will be warmer, and so will the ground on the souther face of your house or other building.
Northern facing slopes, the north side of your house as well as dips and valleys in the ground where cold air can flow to and settle will be also be colder.
So if you have a north slope, and or the south face of your house and the ground in front of it is in full sun during the winter months, you may have good luck with plants that are zoned warmer than your zone.
Oftentimes, many trees and shrubs you can select have a colder hardy variety you can select that will produce similar results to its warmer cousin. It may not be exactly the same taste or texture but if that's what you have to work with, then use what you have.


Imported image is much larger than it in the original Photoshop file

Question: My inDesign document has the exact same dimensions as my layered Photoshop one. In Photoshop, I hid all layers except background and imported that, as a Photoshop file, into inDesign. No problem here. But then, still in Photoshop, I hid everything except a small image, I cropped the Photoshop doc to fit that image size, and imported the result, as a PNG image, into inDesign. Problem: the dimension of the image, which should obviously be smaller than the whole document, is now much larger.
Why does inDesign change its size? It didn't happen when I imported the whole PSD background.
Answer: The problem has to do with a quirk in the png format, the way InDesign handles image sizes and a missing step in your workflow.
The size in pixels per inch of an image is determined by its metadata. A 1000x1000 pixel image can be 300 ppi or 72 ppi or even 2 ppi and it will still be the same 1000x1000 pixels in size. The only difference is the number hidden in the internal metatdata of the image. PNG, however, does not contain any ppi information (it also contains no color profile information, which can land you in trouble if you need color accuracy).
When you import an image, InDesign determines the size of the image (in inches or mm) based on the ppi number in its metadata. Since PNG has no such number, InDesign uses its default: 72 ppi. That means a 720 pixel image will be 10 inches wide if you place it by simply clicking the mouse where you want it to go. At 100 ppi, the image would be 7.2 inches wide, and so on.
This brings up the missing step in your workflow: don't just click. Click and drag to place an image. That way, you determine the size of the image on the page, not the metadata in the image.
Your PSD is probably 300 ppi or greater. Placed in InDesign, it will be sized based on the ppi information in the PSD: pixels/ppi = size. Your cropped PNG has no ppi metadata, so it will be sized using pixels/72 = whatever that happens to be.
In general, don't use PNG as an image format for print unless you know for certain that your document's RGB profile is sRGB and the original image was sRGB before you exported as a PNG. PNG was developed as an image format for the web specifically, so it didn't require a ppi number or a color profile.
Answer: Check the Link Info (on the Links Panel) on the image you imported. Chances are the Actual PPI is the same, but the Effective PPI is different (smaller).
Because you are putting a smaller image into a bigger frame, it is stretching over a larger area. This will cause your Effective PPI to go down.
Try dragging the image into an area on the page that is not already a frame/object. It should import at the original, unstretched size.
Comment: Thanks John, but even when placing the image outside any existing frame it is enormously larger than the original. How frustrating!


Using 3 or more keyboards in Mainstage 3

Question: I'm trying to use Mainstage to create a MIDI-based band at the school that I teach at. I've connected 3 keyboards and assigned them to different patches. Two of the keyboards are the exact same brand and type (M-Audio Keyrig 49). The issue that I'm having is that the keyboards that are the same cannot be mapped to different patches; they play both of them. I tried changing the MIDI channel and that didn't solve anything. Any ideas how I can distinguish between two M-Audio keyboards?
Comment: Yeah, this took me forever to figure out and Apple's documentation is terrible. I have to get home before I can look at what I did and answer your question, but I remember going to the main screen and adding additional keyboards to the view. That probably doesn't make sense but I'll be able to help you out in about 7 hours.
Comment: Thanks for the response. I added keyboards to the setup screen already. I have three there.
Comment: There's some way to control which physical keyboards are connected to which virtual keyboards which are connected to which virtual instrument. I remember dragging some bar across for which notes go to which instrument and I just dragged the bars all way across to make it control all or none of the instrument.
Comment: Ok. Please let me know (when you get home) what the trick is. Thanks!!
Comment: Finally got my keyboards plugged in and failed to figure it out and had to web search on it again. Now next time I forget I know I can just come here! Excellent question! Keep asking MainStage questions and we'll both be experts soon! :-)
Answer: It seems so easy once you know how to do it. I actually couldn't figure it out and had to use my web search skills. A guy named Eric Barfield has a tutorial here:
http://ericwbarfield.com/blog/2014/4/25/tuuca6bxj8hc0r3428m9x8mx07n8rl
What you've already done is gone to the Layout tab, added on-screen keyboards, clicked on them and then selected a separate MIDI port for each one of them.
You would think the next step would be to map an instrument to a keyboard, but no, you go back to Edit view and map instruments to MIDI ports in the channel inspector for the instrument:

Click the instrument channel strip. Under midi input, select keyboard: YOUR KEYBOARD NAME. Do the same with the other keyboard.

If you have three physical keyboards and three different instruments, then you can just select a different MIDI port for each instrument and then each keyboard controls a single instrument.
If you want to play more than one instrument with a single physical keyboard, then first make sure you have an on-screen keyboard mapped to the MIDI port. Then go to two or more instruments and set them both or all to the same MIDI port. Now when you play that keyboard, it will play all of the instruments that have that MIDI port selected. Then you can go to Layer Editor, which is on the Edit screen, click a track and the Layer Editor for the keyboard that the track is mapped to will be an option at the bottom. In the layer editor you can choose key ranges for each instrument by clicking and dragging.
Whew. Probably a little more complicated than it has to be, but that's Apple Professional Creative software for you.
Comment: I'm not sure what was happening with our gear yesterday. I just started from scratch, connected the keyboards one and a time and everything worked properly, which is weird. The tutorial you posted up top was a tutorial I followed when I first started using Mainstage. Thanks for the response.


Factors effecting the force on a current-carrying conductor

Question: Does anyone know why it is that a stronger external magnetic field will result in a greater force on a current-carrying conductor exposed to this field? I'm struggling to find an answer to this that actually explains the physics behind it, rather than just relating it back to the formula F=BIlsintheta.
Answer: In a sense, this cannot be explained.  It is just an observation of how nature works.  We can describe it, but not explain it.
One can come upon this phenomenon as a consequence of other principles, for example, the Biot-Savart law, or from Maxwell's equations.  But none of these are explanations.  You can swim upstream looking for precursor principles to the phenomenon, but you will swim for a long time and never find a starting point.  At some point you stop swimming and decide that you have reached a principle that you will simply have to accept without explanation.
Maybe someday we will know why things are the way they are.  But I doubt it.


How do people camp on ice?

Question: When walking on Hofsjökull glacier in Iceland, I wondered: how do people camp on multi-day trekking trips across icecaps, such as when crossing Greenland?  My primary choice of tightening a tent is to put pins into the soil; this doesn't work on ice.  My second choice is to use rocks to fasten my guy lines; this doesn't work either on an ice cap.  How would I fasten my tent?  And not to forget, it can be very windy on those ice caps and glaciers, as there are no obstacles.
Comment: With snow you can often bury the peg as a deadman. On ice you can cut bolards
Comment: If there is snow around filling a bag with snow and burying provides a good dead man anchor. Expedition tents also have flaps around the base for burying in the snow, and are free standing so guy ropes only provide a part of the overall structural strength.
Comment: My tent is free standing, but there's not always (enough) snow on top of the ice.
Answer: You don't use ordinary tent pegs, you use something a lot more substantial. For example, pictured below are two ice screws (cheap ones I found a picture of on Ali Express), which would work if the ice is hard enough. These screw into the ice and the threads hold them in place.
If you use these, and you leave your tent behind during the day, make sure you cover them with a pile of snow so they don't warm up in the sun, melt the ice, and pull out.
Comment: Don't use to many ice screws. I think 2 is maximum. Otherwise strong wind may damage a tent.

How do people camp on ice?


How can I reset the fuel mileage on my BMW X3 2.5L 05 v6

Question: Car recently went into the mechanic for some repairs, I had a faulty ignition coils and a exaust hole almost at the engine before any censors in the system. The cars computer is reading 19.7L/100km. Obviously this is terrible fuel mileage. I'm wondering if a computer reset could alleviate this fuel issue? My theory is that that cars computer was constantly reading too much oxygen because of the exhaust hole which skyrocketed the fuel economy and now that the problems are fixed the computer is so outdated that it can't adjust for better economy? The ABS censor rings have also rusted off the back axel causing the speedometer not to work properly. Could this also be the cause of these issues? I've read that taking out the battery for an extended period of time will essentially reset the vehicles computer to factory minis the accumulated kilometres. Any suggestions to fixing this problem? Like I said the car came out of the shop no more than two weeks ago so I can't understand why the economy is still so bad. I drive it's aggressively but not enough to cause fuel mileage as exaggerated as 19.7L per 100 km
Comment: If the speedi reading is not correct, then that mileage reading never will be either...
Answer:
Have you reset the mileage on the dashboard (OBC)? You should hold some button down on the fuel economy screen and it should reset. I'm assuming you've done this but the OBC persists in its reading of this high consumption. In that case, does the car actually consume this amount? Try filling the fuel tank, resetting the short-term mileage, driving 50-100 KMs and then topping the fuel tank completely up again. What amount does it take? If the real fuel consumption is within 10% of the OBC economy, then you have a sensor issue somewhere (like an oxygen sensor) or a fuel system issue. If not, the the speedometer error could cause it, but only if it's a really big error.


Lubuntu 14.10 High CPU usage and choppy video playing

Question: I have an Asus Notebook (2007) with 1 gb ram and 900 Mhz Mobile Intel® 915GM/GMS, 910GML Express Graphics. I use Lubuntu 14.10 with about 300 mb memory usage,but the problem is high CPU usage(100 %) especially when I am playing videos. Also video playing is choppy and laggy especially when I am on facebook and I want to see a video. Please help!
Answer: Sadly you are having an awful PC, the cpu worse than the only 1 GB of RAM.
What you installed?
Two must-have for a slow and outdated computer: preload and zram.
So, open terminal and type sudo apt-get install preload zram-config -y
Then reboot and tell me if your computer is in "better shape" ;)


should a contract draft be reviewed?

Question: in software engineering should a contract draft be reviewed by software developers? or it should be left to legal department and to management?
Comment: I'm voting to close this question as off-topic because it is asking for legal advice, not for help with programming.
Answer: The contract is usually of little consequence to the software developers. In my experience it's unusual for a contract to be reviewed by software developers, but is often reviewed by (or at least made visible to) managers of one type or another within the engineering department. The main points of interest for them would be the deliverables, the dates, any penalties and the maintenance/support offered.
The software specification (which can often be an appendix to a contract) should most certainly be seen by developers, but actual review (sign off and/or providing feedback prior to the contract being signed) is often limited to architects, product managers, project managers, technical leads and similar more senior roles.
This will of course vary a lot from company to company and depending what sort of area the software is in, whether it is bespoke software or another roll out of an off-the-shelf product, etc.
Answer: probably a good idea to do a sanity check of any deliverables and scoping or any hard to achieve requirements. - hopefully these could be seperated from the contract itself for a review.
Answer: Depends on the situation and your organization, but it can be helpful to have the engineers or engineering managers who are familiar with the code review and make sure you aren't misrepresenting ownership or rights if you are using third party and/or open-source libraries and code.
Answer: That really depends on how the contract is written.  If the details of what needs to be delivered are integrated into the contract, that should be reviewed by software developers.  Often times this is just an exhibit attached to the contract.  In that case, you would just want to review that exhibit.  The software team should not be worried about the penalty clauses, indemnity clauses, etc. which make up the bulk of the contract, but should be about delivery dates and specifications.

should a contract draft be reviewed?


MongoDb Upsert Deadlock

Question: Is it possible to reach deadlocks on MongoDb upsert operations?
I'm performing a load-test on an upsert operation that looks like:
db.update(
    { foo: {a: 'xxx', b: 'yyy'}, $lt: {"order.date": someDate}},
    {order: order},
    true, false);

Deployed on Azure machine with the official mongodb C# driver. Single instance, no replica-sets or sharding yet.
When I run 5000 of this same update command, split among 200 concurrent threads (2 machines @ 100 threads each), most of the times it will end with deadlocks. I.e. many of the calls never come back. I can see from db.currentOp() via the console, many of the updates are still there, stuck in a locked:true, with lockType:'write'.
Why does this deadlock happen? How is it possible? And how do I prevent it?  Is there any specific guidelines of what kind of operations should be avoided to avoid deadlocks on mongodb?
Is $atomic related to the solution? I don't even know how to set $atomic:true on c#, though it's probably irrelevant to this deadlock issue.
Comment: Upsert is an update operation?
Comment: it's an update with the upsert flag set to true
Answer: $atomic should help
db.update(
    {
        $and: [
            { foo: { a: 'xxx', b: 'yyy' },
            { $lt: { 'order.date': someDate } }
        ],
        $atomic: true
    },
    { order: order },
    true,
    false
);

also, you may want an $and clause.  check your explain for your call to see what indexes are being used, etc...

MongoDb Upsert Deadlock


Were wealthy people and royals of medieval time able to distinguish real diamond/pearl/gold from fake?

Question: Were wealthy people and royals of medieval time able to distinguish real diamond/pearl/gold from fake? or did they rely on jewelers?
Comment: This is a "gemology"(?) question, not history.
Comment: How is this different from today?  Can people today tell the difference or do they rely on professionals?  The second question is not relevant to history; I will delete it and refer you to google.
Comment: @TomAu In what state some science was in the past, IS a historical question. The fact, that some person is not interested in that subject changes nothing on it.
Comment: diamonds were, If I Recall, unknown during medieval times; we didn't have the technology to cut them
Comment: @Gangnus: "In what state some science was in the past" is a better fit for History of Science. We don't want History to be an "overflow" site for questions that are better suited to other SE sites.
Comment: @TomAu Here the question was not on the state of the science, but on the state of common knowledge of the science in two specific social groups. And that belongs to history.
Comment: @TomAu "We don't want..." do you belong to royality? :-)
Answer: (Posting this as a speculative answer, since I doubt there are any credible sources out there to answer the highly specific question in your title.)
Until the industrial age you'd tell gemstones apart using the naked eye (and a magnifying glass if you had one). Synthetic gems weren't a thing until recently, but there were mundane crystals like quartz. It's not easy for an untrained eye to tell cardinal gems apart from mundane ones, so it's highly likely that you'd involve a jeweler of some kind to make sure. (This page has an unsourced story of a buyer acquiring sapphire for the price of quartz. I'd surmise it's an urban legend, but it's nonetheless a concrete example of where confusions might arise.)
As to precious metals, they were used as coinage because they were relatively corrosion resistant and easy to work, so it's sensible to speculate that someone accustomed with using them day in day out might be able to tell e.g. a brass coin apart from a gold coin. (Plus, gold is softer.) Anything beyond that would likely have required some kind of expert too.
(That said, I'm extremely suspicious that you'd encounter many coins made of non-precious metal that masqueraded as gold or silver in the medieval ages. A more sensible problem would have been clipping bits of metal off of genuine coins as described here. They used small balances like this one to detect them.)
Comment: Coins might be one thing, but more complicated objects another. The backstory of Archimedes and the bathtub was that he was trying to find out if a crown was made out of pure gold or if it had been mixed with lead.
Comment: thanks Denis, you have been very helpful, can you recommend a book/source, an unbiased one and one we can trust, about life of common people in medieval time
Comment: @Vikram - I don't recollect ever reading a book that was specifically on that topic, sorry. But you'll find plenty of crunchy anecdotes in just about any book that covers that timeframe.
Comment: You'd encounter ubiquitous coins made of non-precious metals; most governments debased coinage as a way of inducing inflation.
Comment: @Vikram: haven't read it yet, but [Paul Freedman](https://en.wikipedia.org/wiki/Paul_Freedman) wrote a book on medieval peasants that might be worth checking out.
Answer: The legend of Archimedes came to us from the medieval times. And notice, nobody found anything strange, on the contrary, it was natural that a ruler/king asks a specialist to check the item.
I haven't heard or read any mention about some royal family member to obtain a gemology or goldsmithing education. Without that we could only believe in some sacred abilities of the kings.
Counterfeit stones were often found in some historical crowns. Scotland, for example.
What is interesting, the meaning of the word counterfeit was different in the past. If some stone looked as a precious one, it was taken for a precious. For example, in the Czech crown of Charles IV, there are some stones that are not precious by themselves. But they were beautiful and that was enough. In the medieval times they would take artificial rubies for absolutely natural, even if they knew they were made. And any stone that was not a real ruby, but looked as such, and was harder than quartz, would be taken for a ruby, too. They could not tell two stones from each other, so these stones were the same for them. BTW, our science work the same way, only we can distiquish much better.
And only in Renaissance times European kings and aristocracy started to learn. Before that they were interested in theology and war craft at best. In Islam world, on the other hand, the science and art were highly valued. A legend about a king - carpet maker is well known.
Comment: How were artificial rubies made in medieval times or do you mean, hypothetically, if given a ruby that were told had been made artificially, its appearance and other attributes would have been enough for the buyer?
Comment: @Jeff Artificial rubies were not made in medieval times, but other red stones existed. And when they were beautiful as rubies, they were put in crowns.
Comment: @Jeff Yes, imagine that in 15th Century some "alchemist" makes artificial rubies. They have all attributes of rubies, so, they are rubies. That is all. Maybe, if the production would be too great and could displease some important people, they could declare these stones unholy or bad for health or something else, but that would be a shift of the existant common sense. And it was practical enough.


Can you disable the repair cost increasing in Minecraft 1.8?

Question: As you might know, starting with Minecraft 1.8, the repair cost for an item goes up the more it was previously repaired, to the point where the item can no longer be repaired.
Is there a way to revert this change using command blocks?
Answer: The repair cost of an item is saved in the items NBT data, specifically the RepairCost tag. Knowing this, we can easily create a command block contraption that resets this tag.
Simple version:
Create a redstone clock inside your spawn-chunks (I suggest placing it inside a bedrock box), and use it to power a command block with the following command:
/entitydata @e[type=Item] {tag:{RepairCost:0}}

This will add the RepairCost tag to every item that is lying on the ground, including those who never had it, or for which it makes no sense, such as Cobblestone or Logs. I can't think of a better, non-tedious method, however.
Comment: Nice self answer.
Comment: @Tim thanks for linking this from the other question. That question was the one that prompted this question and answer, but I forgot to link it myself.
Comment: You know that this wont work right, the @a will only select all players and cannot select any items. Instead you must use @e.
Comment: @MrLemon I guessed that's what you wanted :)
Comment: @ModDL you are right of course. Now I wonder how I overlooked your comment 7 months ago...
Answer: Updated version from 1.13+
Some commands have been reworked in 1.13, and /entitydata doesn't exist anymore.
Here is a modern, up-to-date solution (works as of 1.16 snapshots even!) using /execute and /data:
/execute as @e[type=item] run data remove entity @s Item.tag.RepairCost

This has the advantage of only removing the RepairCost tag without making any unnecessary changes.
Usage
Drop items, run command, pick items up again, cleared of repair penalty. Optionally stick the command into a command block with a button, drop items, push button, pick up.
How it works:
/execute as @e[type=item] run

/execute causes a command to be run for every item selected by the selector (here @e[type=item]: all entities of a type "item" - dropped items are entities of this exact type)
as makes the command's "executor" the actual entity targeted (as opposed to the player/server who runs it, this will be important later on
run specifies that the rest is the actual command to execute
Now every dropped item "runs" the following:
/data remove entity @s Item.tag.RepairCost

/data is the new command for all your entity and block data manipulation needs, it has very many complex options...
remove specifies we will be removing something
entity specifies we are targeting an entity, you can also target a block or "storage", I am guessing you can use this to store data for later use without tying it to an entity - sort of like included in your world's savefile.
@s targets "self", or the entity executing the command (that's why the as in /execute is important - it makes it so now @s actually selects the specific dropped item).
Item.tag.RepairCost-this simply selects what we want to target for remove to do its work. You can run the command with get instead of remove to show how it works - it will display that particular item's repair cost if it has any. In case of RepairCost, it is stored under the Inventory Item's "tag" list, which also can contain enchantments, damage values, and other extra data, while the Inventory Item itself is stored as an "Item" object on the actual minecraft:item entity.
As a bonus, the command provides instant feedback with the changes that actually occurred - if no items were modified, there is no output, and otherwise a line per item modified is shown.
More details/rambling
The below screenshot documents some of my poking around; lines saying "such and such has the following entity data" are where I used get instead of remove to get a hang of the structure. The first few lines with eggs and salmon items I targeted simply Item, which then returns the typename of the Inventory Item; then I ran Item.tag which technically ran on the salmon and eggs, too, but since they did not have any tags on their Item no message was shown; the Enchanted book had a tag containing a list StoredEnchantments and a RepairCost (getting closer!). Next was the entire command, just with get instead of remove, confirming items with a RepairCost of "1". Next messages ("Modified entity data") is where I ran remove - afterwards the get command did not result in messages as all items with RepairCost were gone now. As a test, I ran the get command with Item.tag as target to see if my pickaxe had a repair cost tacked on, and it didn't - it did nicely show the Damage value and the list of Enchantments.


Adding dimmers to two LED circuits, which have dimmable bulbs - each circuit has three switches

Question: Two existing LED cluster circuits (almost new house) - they have dimmable bulbs (4 & 8 respectively) and three switches each.  Is there only one way to properly wire these circuits?  If not, do I need the original electrician to add dimmers?  If there is only one way to properly wire, can I just add an LED (3way) dimmer at one switch location in each circuit?  Will the circuits then be operable from any switch, but only be able to change the dimmer setting at the one with the dimmer switch? .... hoping it is that simple.
Answer: What you have is two three-way switches with a four-way in the middle. What you need to do here, for each switch set, is

Identify which are your three-ways (one black + 2 brass screws), and which is your four-way (four brass screws). Put the four-way back together, as you're not going to mess with it.
Pick which of the three-way switches you want to replace with a dimmer. It doesn't matter which one you pick
Wire your dimmer up to the three-way, making sure to note which wire was connected to the black screw

Your dimmer will work with the existing switches without any other changes but you can generally only have one dimmer per circuit (unless you buy something specialized)
Comment: If the dimmer needs neutral, and many LED dimmers do, you will need to place it in the 3-way switch location that has neutral in the cable, if any do.
Comment: The (unless you buy something specialized) can lead to some nice options. With Lutron's Caseta series smart switchs one dimmer would replace one of the two 3-way switches. Other switch boxes would have all travelers ganged for pass through to the load. Then those other two switch boxes can have Lutron's PICO remote mounted in a wall mount bracket and be paired to the dimmer. This way you can get dimming and on/off control from all three former switch locations. (Other smart switch technologies may offer differing levels of capability however the Caseta dimmer can be operated without a neutral)


water relief valves on water heater

Question: I have an A.O.Smith water heater. The water heater in my garage has a outlet marked "relief valve" on the side of the water heater near the top, but nothing is connected to it. Instead the water relief valve is connected at the top of the water heater. Why is it so? Now  I am seeing occasional water dripping from the "relief valve" outlet. Is that a problem?
Comment: I'm not understanding from the description - can you post a photo?
Comment: the relief valve is not leaking. The water comes from the outlet marked "relief valve", which did not have a valve installed. Is this simply the case of incorrect installation?
Comment: Nothing is connected to the relief valve on the side of the heater, yet the water relief valve is connected at the top of the heater? I'm very confused! Clear, focused pictures would help greatly. Also, including the actual model number of the heater would help - it would allow someone to look up the documentation for it.
Answer: A dripping relief valve is a problem. Causes include: a failed valve, a faulty thermostat causing overheating, excessive water pressure, or water hammer causing overpressure.

water relief valves on water heater


Authorship change on conference paper after conference program is printed

Question: I am a coauthor on a psychology conference paper that was accepted based on a short abstract. The first author became unable to attend the conference and offered the opportunity to present to the coauthors. I accepted and later found out that I need to prepare the slides and text for the presentation.
The first author had presented similar material to a very different audience (a practitioner audience in a workshop setting in Spanish) and offered me the slides from that presentation. The material needs considerable reworking: it needs to be adapted for a researcher audience; have a theoretical framework integrated; be shortened considerably; and be written in (or translated to) English. I should also say that I made scientific contributions to the overall project and these particular results.
My colleague agreed that given the extent of the changes, I should be first author (up from fifth author where I am currently) and he second (remaining authors unchanged). He contacted the conference organizers with the request, but the conference program has already been finalized.  The first author believes that this means that no authorship changes can be made, but I am not sure.
There will be no conference proceedings, so the conference program is the only documentation, other than the presentation slides and any documents we distribute.
Can authorship changes be made in the presented version of a conference paper even if the conference program is already finalized?  Can we list the paper on our cvs differently from how it appears in the program? Are there any written guidelines on this topic?
Comment: If there are no proceedings, is it really a paper?
Comment: If there is no paper, then there are no authors.
Comment: Why do you care that much about the order of the authors for an abstract+presentation only conference?
Answer: I have very little experience with "talk only" conference papers (and, as jakebeal correctly asks, why is it a paper if there is no paper?), but generally, the ordering of authors (or even who is an author) of a conference submission has very little to do with who prepares the presentation or who actually does the talk.
Rather, the order on papers is usually either alphabetical or by some measure of "who did the most work" for the actual research that is being presented. Hence, a change in who presents a paper (which often happens, due to time constraints, visa problems, illness, ...) usually does not require a change in the order of authors, as the underlying work (and who did it) has not changed.
Comment: Just to clarify, it is quite common to present papers orally in psychology with no published version following. In fact, in my experience psych conferences rarely publish proceedings with the full papers. Thanks for your answer, which helps spell out some of the issues involved.
Comment: @Guest I guess we just find it highly weird to call a conference submission a "paper", if there is no actual paper.
Answer: According to Science,

there are no hard standards for the order of authorship. Most
  institutions have guidelines, but few are written down.

Having said that, the situation varies from case to case. You need to consult with the conference organizers. As far as I know, the order of authors is not generally changed after submission, let alone after acceptance or publication of proceedings. This is also true for extreme situations; for instance, I know of at least two A* journal publications where the first author passed away after submission and the second author completed the article. Still, the original order of authors remained intact.
Also see related questions on the first author and the order of authors in a publication.


Will the Yamaha SB3X-2 French horn silent brass work for a marching mellophone?

Question: I play both French horn and marching mellophone, and was wondering if the Yamaha SB3X-2 French horn silent brass pickup mute would work for the mellophone, so I don't have to buy a second mute end.
Answer: The Yamaha website lists the Silent Brass SBX Series, including the SB3X-2, here:
https://usa.yamaha.com/products/musical_instruments/winds/silent_brass/silent_brass/
There, there is a link to a Compatibly Table for the SBX Series.  Right up the top of this page it says:

The Pickup Mute is not compatible with Piccolo Trumpets, Alto (Tenor) Horns, Baritones, Alto Trombones, Bass Trombones or Marching Brass Instruments.

Also, down the bottom of the page there is a Please Note section, the second dot point says (quite explicitly):

The Pickup Mute is not compatible with Marching Mellophones, Marching French Horns, Alto (Tenor) Horns, or Baritones.

So unfortunately, it looks like the SB3X-2 won't work for your marching mellophone.

According to the Yamaha website the SBX series is actually  discontinued, but even the new SBJ series of pickup mutes apparently doesn't have a model that is compatible with marching brass instruments.


Debugger for Code::Blocks + Arduino

Question: I am not very experienced in this, but I was wondering if Code::Blocks has a way of getting a debugger that runs for Arduino chips, specifically. I understand there is Arduino IDE for but does it allow debugging specific to those microcontrollers (Amtel and such)?
Comment: This is for Mac between.
Comment: The arduino IDE does not support debugging on chip, and it will take additional hardware to do it (like a JTAG). I don't know if Code::Blocks has any support for this kind on chip debugging though.
Answer: Answer: Code blocks does not currently have an Arduino debugger. The Arduino IDE does not have a debugger.
There is an Arduino debugger in Atmel Studio using the Visual Micro plugin.
That said, you have to use Ms Windows to use Atmel Studio which might not be available to you.
The Visual Micro debugger is simple and uses usb so does not require additional hardware but as your experience grows you might also like to progress to fully blown hardware debug using the native Atmel Studio Tools
Visual Micro debug in Atmel Studio
Atmel Studio Download
Comment: Can you suggest a hardware debugger to go with C::B?
Comment: I already answered that question so I am not sure what you are trying to achieve by asking it again. Two of us have tried to help you but you seem to want to ignore the answer?
Answer: If you are interested in on-board debugging or off-board debugging, you will need a programmer/debugger. I would recommend the Atmel AVR Dragon. Atmel AVR Dragon uses the Atmel Studio 6.2, which is a great IDE.

Debugger for Code::Blocks + Arduino


Curled leaves on Jojo plum and something rot like in fruit

Question: We have planted Jojo plum tree couple weeks ago.
Some of tts leaves are curled and there is also something rot like in the fruit. I have not found any aphids in leaves.
We have mostly sandy soil and water quite often.
What is going on?
Answer: Two separate problems; the puckered, curled leaves are caused by plum aphids. most likely plum curling aphid rather than mealy plum aphid. They cause this sort of damage in mid to late spring for a few weeks, but newer growth after that time period is unaffected. Whilst the effects might be unsightly, it doesn't harm the tree, so plum aphids can be tolerated to avoid using insecticides. Info on plum aphid here https://www.rhs.org.uk/advice/profile?pid=681
The fruits seem to have been affected by the larvae of Plum moth - the larvae enters the fruit (you can sometimes see a depressed area on the outside which indicates its in there) then eats usually round the stone, leaving its frass (poo) behind. The fruit you show is only lightly affected; the interior of affected plums often looks much worse and you may even find a larvae/caterpillar inside some fruits - they look pinkish. You can hang a pheremone trap in the tree around May time - when you see its caught an increasing number of moths over a period of time, its time to spray. You don't say what part of the world you're in, but information on plum moth here https://www.rhs.org.uk/advice/profile?pid=554, though the recommendations for insecticide treatments apply to the UK - there may be other treatments in other parts of the world.


Tradition of Boxing Day

Question: In Australia we have a public holiday on 26th of December and call it Boxing day. Why is it called Boxing Day?
Boxing day is a tradition held each year the day after Christmas in the Commonwealth.
Comment: Welcome to History:SE. What has your research shown you so far? Are you looking for something beyond what is in the [Wikipedia article](https://en.wikipedia.org/wiki/Boxing_Day)?
Where have you already searched? Please help us to help you. You might find
it helpful to review the site [tour] and [help]and, in particular [ask].
Comment: See Wikipedia's [Boxing Day](https://en.wikipedia.org/wiki/Boxing_Day).
Answer: Boxing day was used (in the UK) by many landed gentry to give a gift to their staff and/or suppliers as a thank you or payment for the services supplied during the year, this could be money or goods  ie food or materials.
This is an easily searched for topic, but one that I have been interested in as it is also my birthday.
I will let you confirm the information provided...

Tradition of Boxing Day


iOS 7 migration help - Runs in Simulator, but not on device -- app does not load

Question: Disclaimer: I'm helping out on another developer's code (he didn't have the time and the customer wants it fixed quickly) and so I'm not totally familiar with this code.
So the app is built for iOS 6, is in the App Store, and runs great. Until you try opening it on a device running iOS 7 GM. You see the splash-screen for a moment, then it crashes completely. This is causing problems because none of our users can use the app anymore after updating.
I just got the source code and I have been trying to figure it out. It compiles fine, and even runs in the iOS 7 simulator. (Although, of course, the UI needs to be redesigned for iOS 7.)
Here's where it gets weird: when I run it on my iPhone 5 (iOS 7) from Xcode, the app hangs (just like with the App Store version, of course) -- but it's just so weird, considering that in runs in the Simulator.
Good news is that I have some runtime errors that might help to track down the problem. I ran a search that indicates it could be a missing connection in a xib file, but I didn't find one.
Here is the log. If it helps, I can also include the build warnings.
2013-09-20 20:16:55.455 myappname[2514:60b] * Terminating app due to uncaught exception 'CALayerInvalidGeometry', reason: 'CALayer position contains NaN: [nan nan]'
* First throw call stack:
(0x2e3d0e8b 0x386ca6c7 0x2e3d0dcd 0x307d5feb 0x307d5eef 0x307d5e7f 0x30b53517 0x30b6373b 0x30c042f1 0x30b56533 0x307ddf43 0x307d9767 0x30b6b411 0x30b67ed5 0x30be7501 0x30be71a1 0x30c03685 0x30bcf53d 0x30c034bf 0x30b55f3d 0x30b55d19 0x30b55609 0x2ed32143 0x30b55495 0x30b62153 0x30b61bd3 0x30c43e13 0x30c8398b 0x30c83961 0x30c82abf 0x30c82663 0x30c8256f 0x5c4d7 0x30bc7425 0x30bc6e6b 0x30bc14b9 0x30b5bbe7 0x30b5aedd 0x30bc0ca1 0x3303c76d 0x3303c357 0x2e39b77f 0x2e39b71b 0x2e399ee7 0x2e304541 0x2e304323 0x30bbff43 0x30bbb1e5 0x5b485 0x38bc3ab7)
libc++abi.dylib: terminating with uncaught exception of type NSException
Thread 1: signal SIGABRT
I really have no idea what is going on.
Any help would be greatly appreciated :)
Comment: This is awfully non-specific. I mean, have you tried anything at all? Like, say, setting an exception breakpoint and seeing what's causing the layer to have NAN in its position?
Answer: try to use preferredContentSize to define view size.


What does RPM mean in a propellor aircraft, compared to a jet aircraft?

Question: What is the practical significance of speed RPM in a propeller aircraft for a pilot? I am not able to correlate it with RPM in jet engines?
Comment: I don't really understand your question. By "propellor aircraft" do you mean "piston engine"? Or turboprop? How and why are you trying to compare RPM values? Can you give a specific example to help clarify your question?
Comment: @Adder. If you are trying to equate power in a prop aircraft, with thrust in a jet powered aircraft, just knowing the RPM of the prop, and the RPM of the gas turbine, is not sufficient information. So, the answer is, there is no correlation between just these two parameters.
Answer: RPM in a propeller aircraft is typically under 2400, as the prop spins at the engine RPM speed. Above 2700 the tips of the propeller begin going supersonic and make more noise than anything.
Jets engine spin much faster, as discussed here
Which are typical rpm values for aeronautical turbines?
Comment: Just two nitpicks: 1) the prop spins at a multiple of the engine speed, as a lot of them have a gearbox in between. 2) The blade tips will go supersonic at lower rpm if they are longer, so giving just an rpm number as a limit is misleading.
Comment: What @AEhere said (and given the answer's focus, I'm not sure I'd call that just a nitpick). The specific value will depend on gearing and propeller size. As one example, for the plane I'm flying, the magneto check is done with the engine at 4000 rpm, warmup is 2000 rpm, and idle is somewhere around 1800 rpm. (I don't recall off hand what the cruise rpm is.) And of course, while it'll be a *multiple* of the engine rpm, it won't necessarily be an *integer* multiple (and technically it doesn't need to be a multiple >1 either, but I'm not sure what would be the value of a sub-1 multiplier).
Answer: in propeller aircraft, the practical significance of propeller RPM is it is one component of the equation that determines propulsive power, the other being shaft torque.
If the propeller has a fixed (nonadjustable) pitch, then the RPM of the propeller is a simple indication of the power output of the engine, and the pilot manages engine power by adjusting tachometer RPM with the throttle.
Controlling the power output of a turbine engine is a more complicated process, and depending on the type of engine and its application, the pilot may use pressure measurements in the different stages of the engine or ratios of those pressures or shaft RPM's expressed as percentages of full power to manage the power output of the engine.
Answer: There are three primary cases for use of RPM in aircraft that differ by engine type: piston, turboprop and turbofan. In all three cases RPM refers mainly to two speeds, propulsor and engine. They may be indicated in percent of maximum (usual for turbine) rather than as a specific speed (usual for piston).

Piston engine- the propulsor is the prop and the engine speed measured is the crankshaft. Usually there is no gearing and both are the same, so there will only be one gauge in an aircraft. Notable exceptions are warbirds with high power and correspondingly large props.

Turboprop - the propulsor is again the prop and the engine speed being measured is the turbine output shaft, fixed to the low pressure compressor. This is input to a gearbox since turbine speeds are too high to be useful in directly driving a prop. There can be two speed gauges in the aircraft.

Turbofan - the propulsor is now the front fan and the engine speed being measured is usually the core, the high pressure compressor. The front fan historically runs on the low pressure compressor shaft. PW inserts a gearbox between the front fan and the output shaft, making the drivetrain resemble the turboprop configuration. More complex engines may have three shafts, all running at different speeds.


If someone has my email address can they get my IP address?

Question: I'm being stalked and the stalker is a hacker.  If he gets my new email address can he get my IP address from it?
Comment: Is the stalker remote or local?  In another question, you're worried about hacking your wifi network which would require that the hacker be physically close enough to pick up the signal from your router.  If we assume that the attacker knows physically where you live, it's likely that they could get your public IP address (which will likely change over time) but that doesn't in itself create a large security issue.
Answer: The question was answered in the comments and summarized here in case someone else comes searching with similar questions.
The email address on its own won't reveal IP address of Sender.
One needs to have access to email sent from given address and email service provider has added to headers sender's IP address. One should note that many service providers do not add IP address of sender. Further, this applies to only emails sent out from a fixed line connections like Broadband or Leased Line etc. Emails sent out of mobile phone connections usually carry the service providers IP address and location information is out of reach for most people.
Edit: As @scott commented one can always find the incoming mail server IP address for the email address in question. If the given domain is hosted on mail services like GSuite, the IP address of incoming mail server will reveal very little or nothing.


Object Relational Mapping Design Patterns

Question: I want to start building better persistence layers using NHibernate and other ORMs.  What are the best design patterns or important design considerations for implementing persistence with ORM?
Answer: Couple off the top of my head...
1) Be careful not to group data that changes at drastically different rates into the same object.  This can end up bloating tables with redundant data.
2) Avoid throwing in text fields that you intend to search, better to use something like Lucene for this.  DBs aren't as efficient as dedicated text search libraries when doing LIKE style queries.
3) If you can make it so that your objects are immutable once written (i.e. they have a state id), then you can get very nice caching benefits on the front end and keep people from even needing to hit your server in the first place.
Answer: A high frequent design pattern that we use is Singleton. Another things we consider to use is lazy loading and data pagination.
Answer: singleton. very useful but also useful for u wuld be the following link....
http://www.yoda.arachsys.com/csharp/singleton.html


Reduce the laptop weight falls on shoulder when carring

Question: I don't like to use a back pack instead of the side bag supplied by laptop it self. But when I carry the laptop in a back pack for a long distance, I feel a pain on my shoulders. How do I reduce the pain by doing a hack on placing laptop in the bag?
Answer: What might help you is:

Adding cushions to your backpack or shoulder bag straps. This can be done by getting softer straps or sewing softer materials into the strap, also making the strap broader helps. The broader the strap the more the weight is displaced, there are usually devices for this already on the strap.
Get a waist belt. A waist belt for your back pack helps it support the weight instead of just lying directly on your shoulders.

Usually a shoulder bag has more than one handle, it has a longer shoulder strap and a shorter hand strap, by using both of them you lessen the weight directly on you shoulder. Also, switch sides that hold the bag frequently and avoid narrow straps, try broader padded ones.

You may want to invest in a new back pack that is made to hold a appreciable amount of weight. This way the backpack is stronger and more comrfortable.
Fitting you backpack.
hartchirocenter.com

The backpack should fit so the bulk of the weight is transferred from
  the shoulders to the hips and lower back. Shoulder straps that are too
  loose can cause the backpack to dangle uncomfortably, and cause
  misalignment and pain.
Choose a backpack with a lumbar support. The lumbar cushion will
  redistribute weight to the lower extremities, creating a fulcrum that
  facilitates an upright standing position and good posture that is
  essential for proper spinal health.
Answer: Waist, chest, and hip belts on your backpack take significant stress off your shoulders no matter how much weight you are carrying.


Can I save this Northfork Pine?

Question:
I recently re-potted this guy to a pot thang would drain at the bottom and have moved him over the course of a few months to a spot that has more light. The color has continued to get darker and the tip are curling. When I reported it, I watered it throuoghly and haven't watered it again. I have been listing it and have a humidifier going in the room now. Is there anything else I can do? Do you think it'll make it?
Answer: Usually when a Norfolk Island Pine branch tips start curling like that it indicates that at some time the root ball became too dry. If the foliage becomes crispy then it went too far into dryness, otherwise you are in with a chance.
It only takes one drought incident and might have occurred when you transplanted if there was a lot of damage to the root ball that left your tree top heavy, with too much foliage to be supported by the roots. If it continues to look unhappy but does not continue drying (in which case you will see many needles falling) you might consider pruning back the foliage by a quarter or so to allow the root to catch up again. Unlike regular pines the NI Pine responds well to careful pruning if it is still viable.
Probably better to have indirect light and not full sun until it has recovered its normal growth. The higher humidity will help a bit.

Can I save this Northfork Pine?


PHP Extension persistent_list?

Question: I am trying to understand persistence. I see some if statement
<code>if(zend_hash_find(&EG(persistent_list), key, key_len+1, (void **)&rle)==FAILURE)
</code>
I am trying to replicate this code as if it were PHP. I did some research on persistent variables in PHP. All I could find was things that used things like $_SESSION. However, I don't have too much experience in PHP. So, I am uncertain to what functions create persistent connections. However, I am assuming $_SESSION, $_POST, and $_GET, all create persistent connections. Assuming that persistent connections is tied to this list.
Would I have to loop through $__SESSION keys to make this equivalent to the code above? Am I understanding this right?
Answer: Well, I found the answer, again lol.
There is a function in php called apd_dump_persistent_resources.
This will mimic that if statement

PHP Extension persistent_list?


Difference between Site Collection Owners and Secondary Owners in SharePoint

Question: Can anyone help me to find the difference between Site Collection Owners and Secondary Owners in SharePoint Server 2010.
Answer: There really isn't a difference - both have the same permissions.  It is just an option presented to you to ensure that there is a secondary contact/user that is responsible for site collection management.


What is symmetry group of non-linear equation?

Question: I am not very sure if this is a proper question, but I'm trying to investigate what the area of math can offer in researching the differential equation in polar coordinates:
$r'^2+r^2=(kt)^2$, $r(t=0)=0$, k- Const or in other notation:
$r'(\theta)^2+r(\theta)^2=\theta^2$, $r(\theta=0)=0$
Comment: It is not true that the only solution is $r(\theta)=0$.  In fact, this is not even a solution.  The actual solutions (there are two) have power series representations of the form
$$
r(\theta) = \pm k\ \left(\frac{\theta^2}{2}-\frac{\theta^4}{32}+\frac{\theta^6}{768}+\cdots\right).
$$
Comment: It seems that   thenonly solution is $r(\theta)=0$.
Comment: There's Lie theory of (infinitesimal) symmetries of differential equations in hte regular setting. In the singular context you can also have a look at Malgrange's construction of the Galois groupoid/algebroid, intensively studied by Casale.
Answer: As for asking about whether the symmetries of this equation would help you solve it, here are a few remarks that you may (or may not) find useful:
I assume that you want to consider what are usually called the 'point symmetries', i.e., the transformations of the $r\theta$-plane that carry (graphs of) solutions of the equation
$$
r'(\theta)^2 + r(\theta)^2 = \theta^2 \tag{1}
$$
into (graphs of) solutions of this equation.  Now, by definition, the graphs of solutions of (1) are the null curves of the quadratic differential
$$
g = dr^2 - (\theta^2{-}r^2)\ d\theta^2
$$
and, of course, this quadratic differential is positive definite in the open domain consisting of the two wedges where $r^2 > \theta^2$, so there are no null curves in this region.  Meanwhile, in the open region $U$ described by the inequality $r^2 <\theta^2$, the quadratic form $g$ factors as
$$
g = \bigl(dr - \sqrt{\theta^2{-}r^2}\ d\theta \bigr)\bigl(dr + \sqrt{\theta^2{-}r^2}\ d\theta \bigr),
$$
So this region is foliated by two transverse foliations of $g$-null curves, namely, the foliation $F_+$ consisting of the solutions to
$$
\frac{dr}{d\theta} = \sqrt{\theta^2{-}r^2}
$$
and the foliation $F_-$ consisting of the solutions to
$$
\frac{dr}{d\theta} = -\sqrt{\theta^2{-}r^2}
$$
Obviously, the transformation $(\theta,r)\mapsto(\theta,-r)$ exchanges these two foliations,
while the transformation $(\theta,r)\mapsto(-\theta,-r)$ preserves them (and exchanges the two components of $U$).  Thus, it's enough to describe $F_+$ in the region of $U$ where $\theta>0$.
Each of the leaves of $F_+$ in the region of $U$ where $\theta>0$ consists of a graph of an increasing solution of (1) that is defined on an interval $(|a|,\infty)$ and that satisfies $r\bigl(|a|\bigr) = a$ and $r'\bigl(|a|\bigr) = 0$ while $r'(t)>0$ for all $t>|a|$.  When $a\not=0$, one has a parametric expression for $r$ near $\theta=|a|$ of the form
$$
r = a + \frac{|a|^{1/2}}{3}\ s^3 -\frac{a}{12}\ s^4 + \frac{2a^2+9}{360|a|^{1/2}}\ s^5 + \cdots\qquad\text{and}\qquad
\theta = |a| + \frac12\ s^2
$$
when $s>0$.  (When $s < 0$ this is a leaf of $F_-$.)  It is easy to see that each leaf of $F_+$ in the quadrant where $\theta >0$ is not bounded above by any fixed $r$-value and hence each leaf of $F_-$ in this region is not bounded below by any fixed $r$-value.
Thus, if a point $(\theta,r)$ satisfies $\theta>0$ and $\theta^2-r^2>0$,
then there will be unique numbers $x(\theta,r) < y(\theta,r)$ such that the leaf of $F_+$
that passes through $(\theta,r)$ also passes through $\bigl(|x(\theta,r)|,x(\theta,r)\bigr)$ while the leaf of $F_-$ that passes through $(\theta,r)$ also passes through $\bigl(|y(\theta,r)|,y(\theta,r)\bigr)$.
The mapping $(\theta,r)\mapsto \bigl(x(\theta,r),y(\theta,r)\bigr)$ carries this quadrant in the $\theta r$-plane onto the half-plane $y>x$ in the $xy$-plane and carries the $F_+$ foliation to the $x=const$ foliation and the $F_-$ foliation into the $y=const$ foliation.
Now the point symmetry group is clear:  It is the set of transformations in this open quadrant of the $\theta r$-plane that gets carried by this mapping into the transformations of the half-plane $y>x$ that are of the form $(x,y)\mapsto \bigl(f(x),f(y)\bigr)$ where $f$ is a strictly increasing diffeomorphism of the line.
However, I don't think that you will be able to find this symmetry group explicitly without integrating the equations, which, of course, you don't want to have to do because getting help in finding the solutions is why you are interested in the symmetries in the first place.
In any case, it is clear that there are two (and only two) solutions that satisfy $r(0)=0$.  Each is the negative of the other, and one can easily find the Taylor series for the solution whose graph lies in $F_+$ when $\theta>0$ and $F_-$ when $\theta<0$.  It is an even function of $\theta$ and satisfies
$$
r(\theta) = \frac12\theta^2 - \frac{1}{32}\theta^4 + \frac{1}{768}\theta^6 - \frac{1}{49152}\theta^8 + \cdots
$$
as described above in my comment.
Now, because the equation (1) is singular, it is not obvious that this formal power series converges; in fact, one needs a little theorem to prove this.  The best way to get to this is to assume a solution in the form
$$
r(\theta) = \theta^2\bigl(\tfrac12 + u(\theta^2)\bigr)
$$
where $u(0)=0$.  Then one finds that, setting $\theta^2=x$, one has an equation for $u(x)$ in the form
$$
xu'(x) = \tfrac12\bigl(1 - x\bigl(\tfrac12 + u(x)\bigr)^2\bigr)^{1/2}-\tfrac12 - u(x)
= H\bigl(x,u(x)\bigr)
$$
where $H$ is an analytic function near $(0,0)$ that satisfies $H(0,0)=0$ and $H_u(0,0)=-1$ (in particular, $H_u(0,0)$ is not a positive integer).  As such, this is in the standard Briot-Bouquet form, and thus one knows that there exists a unique analytic solution $u(x)$ in a neighborhood of $x=0$ that satisfies $u(0)=0$.  (See R. Gérard, Étude locale des équations différentielles de la forme $xy'=f(x,y)$ au voisinage de $x=0$, J. Fac. Sci. Univ. Tokyo 36 (1989) and the references cited therein.)  This proves the convergence of the formal series for $r(\theta)$.
With a little more work, one can show that this solution $r(\theta)$ exists for $-\infty<\theta<\infty$.
Comment: more terms: $$r(\theta)=\frac{1}{2}\theta^2-\frac{1}{32}\theta^4+\frac{1}{768}\theta^6- \frac{1}{49152}\theta^8-\frac{1}{56623104}\theta^{12}-\frac{1}{3170893824}\theta^{14}+\frac{17}{541165879296}\theta^{16}+\frac{587}{175337744891904}\theta^{18}+ \frac{3151}{28054039182704640 }\theta^{20}-\frac{173}{29389945810452480}\theta^{22}-\frac{2641109}{2844006276185865584640 }\theta^{24}-\frac{6343201}{147888326361665010401280}\theta^{26}+ \frac{29002301}{25765432859454526256578560}\theta^{28}+\frac{24753572807}{83480002464632665071314534400}\theta^{30}\dots$$


What happens if the second reviewer for a conference proceeding keeps missing their deadline?

Question: I have submitted a journal article to a conference proceeding which will be held in June this year. Though I submitted it on time in December and the first reviewer accepted it in the first week itself, still I didn't receive a second reviewer's response. In the online submission system it appears as initial submission status, with the phrase "reviewer missed the deadline" repeated thrice in red color. If I cannot get a second guest editor what will happen to the article? Is it possible to accept an article without a second editor? How long would this usually take?
Comment: Have you asked the conference organizers?
Comment: Here is another opinion : ask the conference organisers...
Comment: Seems like that's entirely up to them and it might depend on the first reviewer's input. Someone else might come along here with more info on how these things normally progress, but I'm doubtful anyone will be able to give you a definitive answer besides the actual conference organizers.
Comment: Really, it seems that you are full of anxiety and so you want encouragement that there is still hope for your article. Sorry, but emotions aside, if you actually want a working solution, then do what the other comments are saying: ask the conference organizers.
Answer: This is not your problem but the conference organizer's one. They have to ensure a proper reviewing process.
Usually, they are contacting the reviewer and apply some pressure. It they still get no review, they acquire a third reviewer as replacement (or a program committee member does it by themselfes).


Is the speed of hash functions a disadvantage when storing hashed passwords in a database?

Question: I know one of the advantages of hash functions is that they are fast. However, I read somewhere (I don't know where exactly)  that the speed is a disadvantage for password hashes when storing them in databases, but why is this so ? Would someone explain to me if being fast is a disadvantage for password hashing and why is this so ? (If possible could you also write some links to websites/papers describing this ?) Also are there other situations where being fast is a disadvantage for hash functions ? Thanks in advance for your help.
Comment: Password databases leak/get stolen, and you want to make it as hard as possible for someone who's stolen your database to recover the passwords. [This blog post](https://medium.com/@cmcorrales3/password-hashes-how-they-work-how-theyre-hacked-and-how-to-maximize-security-e04b15ed98d) is a pretty good intro; also, read [this security.SE Q&A](https://security.stackexchange.com/questions/211/how-to-securely-hash-passwords), [this one here on crypto.SE](https://crypto.stackexchange.com/questions/72918), and [Wikipedia](https://en.wikipedia.org/wiki/Key_stretching).
Comment: It's because the faster you can hash a password the easier it is to brute force a previously hashed password.  You don't want that to be fast, you want that to be slow so that an attacker has more work to do and has to invest more (time, effort, money) in finding the password.
Comment: Thank you very much @Swashbuckler. So the slower the process, the more time it will take for the attacker to brute force a hashed password. Now I understand it. Thanks !
Comment: @GordonDavisson: Convert your comment to an answer. It can be helpful to the others. Comments can be deleted and your good answer in the comment will gone.
Comment: @Swashbuckler: I'd suggest you, too, to convert your comment to an answer. Comment can be deleted. But the answer will remain and can help other people.
Answer: Speed can be an advantage for one reason and a disadvantage for another.
When it comes to password security, the low cpu/memory requirements of a cryptographic hash brings a disadvantage, namely than if records or the database are exposed or hacked, an attacker has minimal work to do in order to brute force those hashes into a plaintext password.
This is because passwords are typically short and have less entropy than the preimage security of the hash function. If the passwords are huge and random, say 32 random letters and numbers, then a single fast iteration of the hash function is more than enough.
For security, you want a "password hashing function" to take as much time (compute resources) and memory as is feasible to slow down bulk attacks. However, this becomes a disadvantage to the server which will compare a hash to the database value, since in most cases that server must compute the hash from a user provided password.
An attacker may exploit that disadvantage by consuming large amounts of resources through coordinated mass login attempts of known or expected usernames, effectively a low bandwidth denial of service attack, the server is so busy keeping up with bogus login attempts that real users cannot login. This can be mitigated by throttling access attempts per IP address, per username, and also adding a delay before a login failure is shown. If the user does not exist, the server should not hash the password, but should return an error with an appropriate delay as if the user did exist, so that an attacker cannot infer the presence of usernames in the database.
PBKDF2 is an extremely common password hash, and at its core routinely uses HMAC, so something like 40000 rounds of PBKDF2-HMAC-SHA256 actually may take around 80000 times longer than a single hash iteration. If the server could previously perform 4 billion hash iterations per second, it may now only be able to do 50000 hashes of PBKDF2 before saturating its CPU completely. If you want no more than 10% of resources allocated to password checking, it would need to be throttled at 5000 login attempts per second... which may sound like a lot, but how many people do you think log into something like Gmail, Lastpass, or Salesforce at around 9am on a Monday?
There must be a balanced configuration and enough hardware to handle all user logins even under heavy load without a noticeable delay for those users, and prevent bad actors from denying service to those users. The strength of the password hash may also need to change over time as the resources of attackers increase, threat models change, etc. The cost of reputation damage may be many times higher than the cost of hardware to perform very expensive password hashes.
Are there other situations where being fast is a disadvantage? Off the top of my head I really cannot think of any, hash functions are typically used as part of a scheme, like digital signatures for example with a computationally expensive asymmetric algorithm involved, the security in that case comes from the size of the hash and the effective strength of the signing key, not the speed of the hash.


Application executable name is different from vshost executable name

Question: I have a problem where my vshost.exe filename is different from my actual application.exe filename, preventing me from debugging the application.
The setup is as follows:
- MySolution
    - Installer.Release
    - Installer.Debug
    - Installer.Testing
    - MyApplication

I'm using Visual Studio 2012, .NET 4.0 and InstallShield LE.
Now, for reasons beyond my control it was decided that the application executable name should contain the environment: MyApplication (Release).exe, MyApplication (Debug).exe, MyApplication (Testing).exe.
This is easily done by modifying the .csproj file to the following:
<AssemblyName>MyApplication (Release)</AssemblyName>
<AssemblyName Condition="'$(Configuration)' == 'Debug'">MyApplication (Debug)</assemblyName>
<AssemblyName Condition="'$(Configuration)' == 'Testing'">MyApplication (Testing)</AssemblyName>

When building the application in Debug it generates the following files in my bin/Debug folder:
MyApplication (Debug).exe
MyApplication (Debug).exe.config
MyApplication (Debug).vshost.exe
MyApplication (Debug).vshost.manifest

So far so good.
When building the application in Testing, it generates the following files in my bin/Testing folder:
MyApplication (Testing).exe
MyApplication (Testing).exe.config
MyApplication (Debug).vshost.exe
MyApplication (Debug).vshost.manifest

As you can see, the vshost files that are generated are named differently, which causes Visual Studio to throw the following error when trying to debug:

Visual Studio cannot start debugging because the debug target
  'D:\Code\MySolution\MyApplication\bin\Testing\MyApplication (Debug).exe'
  is missing. Please build the project and retry, or set the OutputPath
  and AssemblyName properties appropriately to point at the correct
  location for the target assembly.

Interestingly, if I change the AssemblyName of the Debug configuration to MyApplication (Foo), then the vhost files in the Testing folder are also renamed to MyApplication (Foo). So something is forcing the use of my Debug configuration onto my Testing configuration. But what?
Currently I can work around it by launching the application and then attaching the Visual Studio debugger, but it's wasting my time. It's also not a problem when building the installer, because the vshost files are simply ignored.
So far Google has not been really helpful. Most of the search results explain what a vshost file is and how it works but that's not what I need. I need to know why the vshost files are named differently and how I can fix this.
Answer: Another workaround can be to disable the vshost option:
Go to Project + Properties, Debug tab, un-check the "Enable the Visual Studio hosting process" option.


What can a spellcaster do to protect against a thunderstone?

Question: As a low-level spellcaster, what can be done to counter the deafness from a thunderstone? Either by protecting against deafness, circumventing or removing the effect.
Comment: Can you clarify in your question what you mean by *low-level*? For example, the game changes massively between 1st and 2nd levels, so if you like the first third of the levels, 1st through 7th say, answers might focus more on the post-1st situation, while if you mean 1st level or 1st through 3rd or something, then the 1st-level situation becomes much more significant.
Comment: While there are a few ways to protect against a thunderstone (per your title), the body of your question asks how to counter the deafness from a thunderstone, which is a different question. Which of those two questions do you want us to answer?
Comment: @Cellion I think the question is pretty clear that any way to avoid suffering from deafness when an enemy throws a thunderstone, whether that be by somehow blocking or redirecting the attack or protecting yourself against deafness, would answer the question. Which *could* be kind of broad, except I don't really think there are a *lot* of options here.
Comment: @KRyan with low level I was thinking of 1st-2nd level
Comment: but could be higher to add more options. Yes anyway to either avoid the attack, or remove the effect of deafness. I will update the question later to reflect the that.
Answer: Here are a few different ways to either protect yourself from a thunderstone or ignore its effects:
Earplugs - Grant a +2 bonus on your save against the thunderstone's effect, and are inexpensive enough for any low-level character.
Forced Quiet - This spell can we cast on someone to protect them against sonic effects, like those of a thunderstone. It grants them +2 on their save, stacking with earplugs.
Remove Blindness/Deafness - If you're already deafened, this 3rd level spell (cast by a friendly caster or from a scroll) will clear it without waiting out the full hour.
Spells without verbal components are not affected by being deaf, including the deafness induced by a thunderstone. If you expect to be deaf, you can use the Silent Spell metamagic to remove verbal components from your spells. Alternatively, the Deaf curse Oracle gets Silent spell for free on every spell they cast.
Comment: +1 good answer, but for a low-level spellcaster I think the *forced quiet* or *remove deafness* spells are more expensive than they are worth.  Better to take the 20% spell failure chance from being deaf than to spend spells or scrolls on these preventative measures.
Comment: @DanB That would be a very tough call. Spell slots are at a dire premium for low-level spellcasters, no question, but *actions in combat* are at a dire premium *always, for everyone*. If you are already deaf and expecting to go into a fight, saving a spell slot by refusing to cast *remove blindness/deafness* could easily get you killed. At least with the spell slot burned, you can still do *something* with your turn, and plan knowing you won't have that slot. If you try to cast something else while deaf, you have a 20% chance of doing nothing at all.
Answer: As Cellion suggests, if you're worried about this attack, you could wear earplugs.  This item gives +2 to your save against sonic effects but -5 to hearing-based perception checks.
Other than that, for a low-level spellcaster, you shouldn't spend resources defending against this attack.  This attack inflicts on you a 20% spell failure chance for an hour.  If the combat lasts five rounds and then you can rest for an hour, then on average you will lose only one spell from being deafened, and you might not even lose that if you fail your save.
It's not worth it to prepare silent spells, to spend a spell slot on forced quiet as a precaution, or to use a third-level spell scroll on remove deafness.  Just be glad that the enemy didn't do something more effective with their ranged attack.
Comment: In the end I choose to accept the answer by Cellion, as it most directly answer the question I asked. But the question I probably should have asked, is what a spellcaster should do to prepare against it, in which case I agree with you reasoning that it is not worth it. I guess I was just alarmed when I saw the duration of an hour, and erroneously thought of that as 600 rounds of combat.


Get To Android Pie bluetooth Settings Without Turning Them Off

Question: Is there an EASY way to get the Bluetooth settings without turning them off?
The new shortcut in Pie sucks because it an on/off button
The old design allowed you to click on the name under the icon to get to the settings to just disconnect one item if needed
Answer: Try long press on the shortcut icon, without lifting your finger until the new screen starts to appear.
On my Pixel 2, I was able to get to the Bluetooth Setting screen.
Answer: Yes hold your finger on it. It also works for Wi-Fi.
(BTW I find it really inconvenient since the screen on my new phone is so slippery, it's hard to hold my finger on one spot. But that's what it is...)


Uncertainty Calculation: Applying Product Rule instead of Power Rule

Question: I use $\delta$ to represent absolute uncertainty. The power rule for the calculation of relative uncertainty in $t^2$ is
$$\frac{\delta (t^2)}{(t^2)}=2\left(\frac{\delta t}{t}\right).$$
But if I treat the power as a product and apply the product rule, I have
$$\frac{\delta (t \times t)}{(t \times t)} = \sqrt{\left(\frac{\delta t}{t}\right)^2 + \left(\frac{\delta t}{t}\right)^2} = \sqrt{2\left(\frac{\delta t}{t}\right)^2} = \sqrt{2}\left(\frac{\delta t}{t}\right).$$
Am I making a mistake? If not, how is this inconsistency reconciled?
Comment: Related: https://physics.stackexchange.com/q/59628/2451 and links therein.
Answer: The product rule assumes that the things being multiplied vary independently of one another, which is clearly not the case when multiplying something by itself. As such, the power rule is the correct one here.
Comment: @BoundaryCondition Adding uncertainties in quadrature (square root of the sum of squares) is the specific step that assumes independence.
Comment: Thank you. In what part of the derivation of these rules is this assumption necessitated? Or is it not and we just find that these rules are only consistent with independent variables?
[I'm staring at the propagation of error formula with partial derivatives.]
Answer: As was pointed out by Sandejo's answer, uncertainties only add in quadrature if the two quantities being measured are uncorrelated.  The formulas for propagation of uncertainty have additional terms that must be included if the variables' uncertainties are correlated.
Specifically, suppose we have two quantities $A$ and $B$ with uncertainties $\sigma_A$ and $\sigma_B$ and covariance $\sigma_{AB}$.  Then the uncertainty in $f = AB$ is [given by]
$$
\frac{\sigma_f}{f} = \sqrt{\frac{\sigma_A^2}{A^2} +  \frac{\sigma_B^2}{B^2} + 2 \frac{\sigma_{AB}}{AB}}.
$$
Uncorrelated uncertainties have $\sigma_{AB} = 0$, and so you end up with the "addition in quadrature" formula you're familiar with.
On the other hand, suppose that $A$ and $B$ are perfectly correlated (as they would be if they were secretly the same variable, which you're calling $t$.)  In this case, it can be shown that $\sigma_{AB} = \sigma_A \sigma_B$, and so
$$
\frac{\sigma_f}{f} = \sqrt{\frac{\sigma_A^2}{A^2} +  \frac{\sigma_B^2}{B^2} + 2 \frac{\sigma_{A}\sigma_{B}}{AB}} = \frac{\sigma_A}{A} + \frac{\sigma_B}{B}.
$$
In particular, if $A = B = t$, then you have
$$
\frac{\sigma_f}{f} = 2 \frac{\sigma_t}{t},
$$
as one would expect from the power rule.


Why is the limit of subdomains in DNS at 127, and character limit at 255?

Question: I couldn't find an explanation to why this is so. Is there something silly I'm missing?
Comment: https://www.ietf.org/rfc/rfc1035.txt section 3.1
Answer: This is to do with the original request for comment (sort of a pseudo standard for internet things) which was based on the limitations of the original technology. We have gotten to the point that by and large the underlying technology of DNS would support more than 127 zonefile recordsets and more than 255 characters however the limitations of the DNS protocol itself (which was based on the RFC) mean that these limitations are still in place.
Additionally even though technology marches on there are still places, especially larger or more well established places online (think major tier 1 and 2 networks) where they are using older generation hardware and DNS software to do the job where these limits are still an issue.


How to implement OAuth2 server with CherryPy?

Question: I am using CherryPy serving up information through a web service. I want to restrict access to some of the functions utilizing OAuth2. I see an example of an OAuth2 server at https://github.com/simplegeo/python-oauth2/blob/master/example/server.py , however, it utilizes its own webserver. How can I integrate this with adding support to CherryPy?
Answer: here is CherryPy example application which using it: https://bitbucket.org/Lawouach/twiseless/src