Bacon/pork fat to replace shortening in rolls?

Question: I don't have shortening and was wondering what pork fat would do to the texture of my crusty rolls?  Can pork or bacon fat be used to replace shortening in rolls?
Comment: What ratios are we talking about? Please [edit] your post to include the recipe.
Answer: Absolutely, it make give it a  smokey but pleasant after taste but I in some ways prefer it to commercial lard. All bacon fat is, is a type of lard anyways done with typical dry heat such as a skillet or pan. It is arguably the best replacement you can use when making such dishes.
Answer: Yes, animal fats such as lard or rendered bacon fat may be substituted for shortening. Really, shortening is a substitute for animal fats in the first place!
Lard and bacon fat do have a lower melting temperature than shortening, but for a kneaded dough, rather than a pastry dough, which is what I'm assuming you mean when you say "rolls," this difference is immaterial.


Redundant email server

Question: what happens if 2 mx records are assigned the same priority levell?  will the email be sent to both places?  Will neither get it? What is the best pratice to have automatic redundant email servers at different locations?
Answer: As for the first question, 2 MX records with the same priority will basically be handled like a round-robin.  Mail will only be handled by one MX for the domain.  This case is specifically discussed in RFC974
Comment: Note there there are plenty of broken MTA's out there. Some only mail to the first result provided by DNS. Some sequentially step through all results regardless of priority. Some consider the priority backwards. I've seen all three behaviors from legitimate sources (i.e., not spammers).
Answer: The best way to resolve this. i.e. the least amount of effort is to setup the primary mail server to be of higher priority. You would then configure your secondary server to function as a store-and-forward backup server (i.e. it does not process any mail but waits for the primary to come back online and forwards to it for processing)
However... There is really very little benefit in doing this most of the time. Most, if not all MTA's will hold email that it cannot deliver for a relatively long period of time - usually several days. If you have a reasonable guarantee you you will be able to resolve any issue with the primary box and bring it back online within a few hours, don't bother with a backup mx record with a mail server.
There is a reason for this. A store and forward backup server is a target for backscatter spam i.e. mail that gets delivered to a spoofed sender because the to: address was invalid - but this was only discovered when the backup tried to deliver to the primary. The server then merrily tries to deliver the email back to the spoofed sender.
If you are concerned about hardware failure, have a backup server ready to go and on failure of the primary, just replace it with the backup.
If you are concerned about network failure and you have a secondary network, plug a second nic into the mail server and set the secondary MX record to point to that ip.
If none of the above works OR if you are looking to load balance a large amount of mail, you should really try and keep both the servers in sync with regards to configuration, user accounts and spam prevention tools. Otherwise, you could end up various different problems.
Answer: Your main server should (usually) have a unique MX priority. Otherwise you end up with mail entering at random entry points. The backup mail servers may have equal priority among each others, and this could be useful, e.g. if you want to balance the load among them in case of main server failure.
For most situations, a single backup server is fully sufficient, provided it is sufficiently independent (uplink-wise). In fact, mostly it is sufficient to rely on the mail server on the sending side to buffer mail and retry when your server is back up. But you have a lot of better control to quickly transmit the backupped mail if you have a backup mail server under your control. On the other hand, it may even be harmful in case of prolonged (say, a full day) main server failure, if the sender thinks that the mail transmission went okay and there is no need to switch to a phone call for urgent matters (as they might do after warning messages by their own mail server).
Of yourse I don't have to tell you that all backup mail servers must be configured properly to actually relay your domain.

Redundant email server


What is deference between wallet address and account address?

Question: I'm new in Ether world. I want to make mini Crypto exchange site with 2 coin ETH and BTC. What is deference between wallet address(maybe It's called Main Ether address) and account address ? or it's incorrect question ? Please give me right and more details way to understand what's happen. Thank you
Comment: Looks almost identical to https://ethereum.stackexchange.com/q/68350.
Answer: If I understand the question correctly, I think they are the same thing.
From Mastering Ethereum:

Ethereum has two different types of accounts: externally owned accounts (EOAs) and contracts

I think you're just describing 2 EOA's. These are just addresses at which ether can be held.
Comment: Thank you for response, but I'm interested, Exchange must have one wallet and other accounts will create by this main wallet ?
Comment: I suspect there are lots of ways to tackle creating an exchange ;) But you could have a single wallet generate many accounts, yes.
Comment: Can you link me sources ? My I create EOA for all customer?
Answer: In ethereum wallet address and account address, both are the same. we commonly say it as wallet address bcoz we import the key pairs(public and private keys) into wallets like metamask or scatter. Now the public will be called as your wallet address as well as ur account address. Hope this will help you.
Comment: Thank you, I want to make exchange, how can I create exchange account ? I Image that exchange must has 'main' address and when one my system's user want's to withdraw some ETH to other exchange account, system must transfer coin from 'main' account


Google Chrome no longer treats " Web Apps" specially

Question: I'm running Google Chrome (Dev Channel), with the <code>--enable-apps</code> flag, in both OSX and Ubuntu. I have four or five WebApps installed, and they appear in the "New Tab" page just fine.
The problem is that, before, when the feature first became available in the Dev Channel, the actual tabs hosting the webapps received special treatment; they would have 3D Dock-like look, and (more importantly) the tab bar would be hidden while using that tab.
Sometime in the last few weeks, however, it seems that the special treatment just disappeared with one of the daily updates. The webapps still show up in the New Tab page, they still work in the sense that they capture all URLs going to that webapp, and they use the right icons; but they've basically become indistinguishable from just a regularly pinned tab. The two special features mentioned above have disappeared, on both Ubuntu and OS X.
My questions are simply:
a) Does this happen to anyone else? When exactly did it begin?
b) Why did Google regress the feature?
c) Is there any flag I can enable to get it back?
Answer: a) You can right click on the tab and deselect show toolbar to remove that (works on windows).
b) and c) I have no idea.


How much mathematics did Van Leeuwenhoek know, and did he use mathematics in this fabrication of lenses?

Question: I've read this article, and I know that he made lenses but it's not clear what tools he used to build them. Specifically, if he used mathematical tools of if he did that only by trial and error. I was unable to find a copy of the references in the end of the article.
Comment: I do not know the answer to your question, but note that the Dutch Wikipedia page says: *"His scientific status was completely dependent on his exclusive knowledge of lens production, and he took great care to keep his methods a secret. Perhaps he made his lenses from the little bit of glass that remains on the end of the blowpipe after glassblowing."* (translation mine).
Answer: The same Wikipedia article only mentions that he "attended school" for a short time. After that he became a bookkeeper's apprentice. So he probably learned some
mathematics at school and as a bookkeeper's apprentice. Then we learn that he was appointed a land surveyor, which certainly requires more mathematics. This implies that he learned somehow the necessary mathematics for this job. Either at school or (more likely) by self-education.
There is not so much mathematics a lens maker has to know, besides what a land surveyor has to know.
Most 17s and 18s and 19s century craftsmen who made important inventions had no formal mathematical training (I mean at the university level). They were self-educated, and they knew enough mathematics for their trade. I mean people like
Jost Burgi (one inventor of logarithms), James Watt, or   John Harrison (chronometer), and many others. They obtained the necessary mathematical knowledge in the process
of training for the trade and self-education.


Are there writing systems with more than upper case and lower case?

Question: The English alphabet has two "cases", UPPER CASE and lower case. Japanese hiragana has one case. Are there any writing systems, with, say, 3, 4 or more cases?
Comment: You'll have to explain a bit better what you mean by a *case*.  Are hiragana and katakana two cases of the same alphabet?  Is italic a different case from roman?  Why or why not?
Comment: Italic or bold or underlined are not cases. Hiragana and katakana are better examples as they could be used as cases but in practice they are not.
Comment: So if I had to explain the Latin cases I would describe it as two sets of gylphs where which one is used depends on word class and sentence position. Are any of the other suggestions parallel to that?
Comment: @hippietrail, I'm asking about capital letters vs small letters.
Comment: OP: are you talking about the positions of the cases of type on compositors' desks or are you talking about the everyday sense of capital letters vs "small" letters?
Comment: This question needs a much more rigid definition of 'case'.
Comment: @curiousdannii: More rigorous than majuscule and minuscule? Anyway it seems to me that the OP is looking to better understand both the term and the concept so answers should help us reach a definition rather than artificially restricting the definition too far before trying to answer.
Comment: @hippietrail That's fair, but the way it is now is just turning into a popularity contest. There's no sign of a consensus being reached, and the answers include things such as entirely distinct sets of gylphs, type face alternations like bold and italic, ligatures, and positional variants.
Comment: Well minuscule and majuscule are entirely distinct sets of glyphs (for some definition of "entirely"). With one distinct function being to distinguish the first letter of a word in various contexts. This rules out bold and italic and leaves katakana vs hiragana and positional variants somewhere in between.
Comment: I think "small caps" might be counted as a third case in English writing.  See https://en.wikipedia.org/wiki/Letter_case#Case_styles, where it is called a "case style".
Answer: The Georgian script has the resources to have three cases, since it has three distinct complete sets of glyphs to cover the same single set of sounds. Yet in practice Georgian is almost always unicameral and only occasionally bicameral.

Asomtavruli, also known as Mrgvlovani (Ⴀ, Ⴁ, Ⴂ, ...)
Nuskhuri (ⴀ, ⴁ, ⴂ, ...)
Mkhedruli (ა, ბ, გ, ...)

Asomtavruli was the original form, Mkhedruli is the current form, with Nuskhuri occupying an intermediate place in history. This is only a bit more complicated than how the Latin alphabet evolved the "uppercase" letters at one stage of history with the "lowercase" letters evolving much later. Only later still were the two actually used together as true upper and lower cases. Before this Latin script was unicameral.
Even though Georgian has been mostly unicameral through history, there have been bicameral uses too:

In Nuskhuri manuscripts, Asomtavruli are used for titles and illuminated capitals. The latter were used at the beginnings of paragraphs which started new sections of text.
Nuskhuri was augmented with Asomtavruli illuminated capitals in religious manuscripts. The combination is called Khutsuri.
Georgian linguist Akaki Shanidze made an attempt in the 1950s to introduce Asomtavruli into the Mkhedruli script as capital letters to begin sentences, as in the Latin script, but it didn't catch on.
In my own experience, some software on some operating systems treats Georgian as a bicameral script so that if you use the uppercase function on normal, Mkhedruli, script it will change letters to Asomtavruli in a way not really done in Georgia. This is probably due to Unicode capitalization tables created by somebody without a full understanding of Georgian and those tables being used in other projects.
Comment: This is an interesting observation, even if not exactly like upper case and lower case in Latin scripts. Syriac works very much like Georgian: the Old Syriac (Estrangelo) script is used for chapter headings alongside West Syriac (Serto) or East Syriac (Nestorian) script in the body of the text. Also in Arabic you can find illuminated manuscripts using (pseudo-)Kufic in the superscriptions and Naskhi in the body of the text.
Comment: Aha and your two observations here are also interesting. I hadn't been aware of them before. I was kind of thinking and wondering about Kufic when thinking about one of your other comments. Personally I wouldn't count using one for headings as case rather than style or font, even for Georgian. It's possibly a common step between unicameral and bicameral though. I do think illuminated capitals from a different glyph sets are much more related to case as we now think of it.
Answer: English and other Latin-script writing systems have upper case, lower case, italic, bold etc. Arabic has as many as four different forms for each letter (initial, medial, final, isolated). It is all a question of how you define "case".
Comment: As I said, this all depends on what you mean by "case". When type was set by hand the capital Roman letters were kept in the upper case (box) on the compositor's desk, the miniscule Roman letters in the lower case, the Italic letters in another set of cases, and so on.
Comment: Arabic's positional forms are not related to any definition of *case*. They are completely analogous to the ways the same letter in any other cursive script join together, including English. It's just that in Arabic it's a bit more stylized and standardized as cursive is the main/only way to write it.
Answer: Perhaps no for the "normal" sense, but in some other important senses there is a kind of yes answer:
There are languages which use Latin script with some extra digraphs or ligatures not present in English. Of these there are a couple in which some of those digraph or ligatures have three case variants, but only by one way of looking at case:

Lower case: dž, lj, nj, dz
Upper case: DŽ, LJ, NJ, DZ
Title case: Dž, Lj, Nj, Dz

This is a kind of corner case that might only come up in typesetting and computerized fonts since the title case digraphs and ligatures are obviously made up of an upper case initial letter plus a lower case final letter.
There are a lot more analogous glyphs in Ancient Greek, where certain letters could be written as diacritical marks depending on upper vs lower vs title case. This stuff is pretty confusing and I make no claims to understand it. Here are the Greek glyphs that Unicode categorizes as "Letter, titlecase":

ᾈ, ᾉ, ᾊ, ᾋ, ᾌ, ᾍ, ᾎ, ᾏ, ᾘ, ᾙ, ᾚ, ᾛ, ᾜ, ᾝ, ᾞ, ᾟ, ᾨ, ᾩ, ᾪ, ᾫ, ᾬ, ᾭ, ᾮ, ᾯ, ᾼ, ῌ, ῼ
Comment: The [wikipedia page on
ligatures](http://en.wikipedia.org/wiki/Typographic_ligature) is quite
interesting. They seem mostly derived (like Greek and Latin lower
case) from hand writing evolution, and possibly merging of letters
into new glyphs as for the "&" which is originally "et". However, I do
not think they have a structural role, especially grammatical, and are more
a matter of style. This can be observed in printed books using the
Latin alphabet, where the use of ligatures is associated with specific
fonts.
Comment: @babou: Exactly. It's not a third case in the "normal" sense. But it's a third case in some important senses. I should add a first line that says pretty much just that ...
Answer: I do not know too much about more than 2 cases, except for one
language (see answer end), but only one case was quite common, and,
from what I read, the use of two cases is historically fairly recent, at least for writing with Greek or Latin origin.
From what I learned in another question, some (at least) ancient
languages, such as Latin or Greek, had only one case. What is now
taken as lower case was the everyday fast scripting for common tasks,
while important books, documents and monuments used exclusively the
well formed version now known as uppercase.
This is for exemple quite clear with the letter Xi. The well formed
version, used on monuments is Ξ, which is not so easy to write as it
has 3 separate lines. The cursive version was ξ, which is clearly a
way of writing the three lines without raising the stylus, when you
are trying to write fast, even if it does not look as nice.
The wikipedia article on this topic states:

Both majuscule and minuscule letters existed, but the difference
  between the two variants was initially stylistic rather than
  orthographic and the writing system was still basically unicameral: a
  given handwritten document could use either one style or the other but
  these were not mixed.

The syntactic uses of cases and  capitalisation is a fairly modern
practice. Actually, despite modern usage, the ancient distinction is
more a difference of font (letter style) than a difference in case
(orthographic forms of a given font).
And fonts kept evolving, new ones being created, throughout history,
as shown in the wikipedia chart. But they are not seen as distinct cases.
Neither are italics, bolface, underlined, barred or shadowed variants, which are also stylistic, though sometimes used to convey a technical intent, rather than obey a grammtical rule.
When discussing these issues, it is probably important to distinguish orthogonality of the existing variations (as in lowercase-italics-boldface-times font),
and the uses made of these variations.
Now, if we consider the case of Greek, written as we do now with two
cases, it does have variants for some letters that could be seen as
additional cases. This is the case in particular for sigma, with
uppercase Σ and two lower case σand ς, the second (lunate sigma) being
used when ending a word. There may be others, but I am no expert on Greek.
Comment: I was going to mention variant final forms too. Another writing system that has more of these than Greek does is Hebrew: `כ` -> `ך`, `מ` -> `ם`, `נ` -> `ן`, `פ` -> `ף`, `צ` -> `ץ`. In fact there's even a Wikipedia article on "[Final forms](https://en.wikipedia.org/wiki/Final_form)". When I was trying to study Traditional Mongolian script there were even differences between syllable-final and word-final forms of some letters!
Answer: As a type designer I consider Latin (and Greek and Cyrillic) to have four cases:
1 Uppercase 2 Small Caps 3 Petite Caps 4 Lowercase.
All four cases may exist in all weights (Light, Bold) and also in Italic.
Small caps are supposed to be higher than the lowercase x-height and are often used in abbreviations and subheadings, Petite Caps have exactly the height of the lowercase x, and are used in Phonetic extensions, e.g. u0262 u026A u0274 u0276 u0280 u0299 u029B u029C u029F but also in rich typography. Luc(as) de Groot
Comment: Unicode may assign them differently, but there are really still just two cases because the glyph shapes are the same for all of the Uppercase variations.
Answer: No, there are no writing systems nor languages which employ more than two cases (sets of aesthetically coherent unique forms of each letter) the use of which goes beyond style and even augmenting or clarifying meaning.  While some freedom of their usage exists, a set of formal rules prescribes certain obligatory usage scenarios which also carries syntactic and grammatically significant information.
This question has generated an interesting thread with some insightful and interesting observations and perspectives.  A great deal of confusion and misunderstanding (or misinformation/ignorance) has also been revealed.
Most of this could have been avoided by a careful and thoughtful reading of the question.
The OP's misidentification and association of the Latin script with the English language gives implicit specifications of the type and scope of information solicited and expected.
That being: a system of letter/character cases whose usage has a linguistic and grammatical component which is not considered optional.  Another important aspect of cases is that they are complete sets of different forms of the same letters/characters (not glyph variants, contextual alternates, positional/decorative forms, or different characters of parallel/historic systems), and their distinction is recognizable to even someone unfamiliar with the script because of the shared characteristics of each case.
(For instance, even without knowing or being able to read Cyrillic or Armenian, I don't think anyone reading would have trouble picking out phrases, words or even individual capital letters from text of either script – even if we can't enumerate all the distinctions like a type designer.)
I was quite surprised by the amount of discussion about features of writing not even closely related to cases.  But I was very pleased to learn of the origin of terns "upper" and "lower" cases!  In fact, in a sense – in the original sense of the common use terminology,  there are/were more than just two cases (storage containers)  for the Latin script; however, that does not apply to the originally asked question.
While the Japanese Hiragana and Katakana are complementary sets of character forms representing the same set of phonetic elements which share aesthetic characteristics specific to each group, and they have interesting, distinct usage protocols as well which is required and not interchangeable; their shapes are not related or linked in any way which excludes them from being cases.
But each set does have two forms with similarities to our cases...  They have half and full width forms of each character some of which differ in their shapes in ways that is definitely parallel to how upper and lower case letters are related.  But this doesn't carry any of the information or meaning that the uses of capital letters impart.
Actually, most of the world's writing systems do not have cases, or any feature that resembles that feature.  Of course, many other writing writing systems are far more complicated & extensive that the Latin alphabet often requiring dozens or even hundreds of unique ligatures and various other contextual forms and for them to be represented/displayed in print or by computer software.  Many require specialized, complex rendering engines which must process and analyze the input information with intricate rules & algorithms which re-order and store the data internally in a particular, canonical abstract form which is distinct from the characters used to display or print it so that the text may be dynamically edited.
While our concept and use of letter cases has become an integral aspect of our written languages it is actually technically a superfluous and unnecessary convention which could be abandoned without losing or altering the underlying basic information stored, communicated or expressed in the text.
However, it is interesting to note that while most writing systems (present & past) are unicameral, but the systems which do – particularly the Latin alphabet – are used extensively around the world and have influenced developing scripts and have been adopted to encode numerous spoken languages which means that the majority of text (in printed, handwritten, inscripted/engraved, or in digital form) which exists in the world is encoded using one of the bicameral alphabets.
Comment: the existence of half and full width forms is not really a japanese language thing, just a computing thing. there are full width latin characters. https://en.m.wikipedia.org/wiki/Halfwidth_and_fullwidth_forms


What is the correct definition of a bad bishop?

Question: Is a bad bishop a bishop that is trapped by your own pawns? (For example, all your pawns are on dark squares, so the dark squared bishop is bad.)  Or is it when your opponent's pawns trap your bishop's mobility?  (For example, they control the dark squares which your bishop controls, so the bishop is bad).
Comment: I updated my answer, I hope it helps! Cheers!
Answer: When evaluating a bishop, there are two totally separate things that must be considered.  The first is whether a bishop is "good" or "bad".  These are very much misnomers because they have nothing to do with the worth of the bishop.  The second consideration is whether the bishop is "active" or "inactive".  Finally, there may be mitigating factors as well (is the bishop doing something useful?).
Good vs Bad
A good bishop is on the opposite color as its pawns.  A bad bishop is on the same color as its pawns.  For example if the white pawn structure is c3, d4, e3, f4, then the light squared bishop is the good bishop and the dark squared bishop is the bad bishop.
Active vs Inactive
An active bishop is outside of the friendly pawn chain (in the above example, if the bishop is on e5, then it is clearly both active and bad).  An inactive bishop is trapped by pawn chains - either the player's color or the opponent's.
Mitigating Factors
There are two main mitigating factors.  The first can be remembered by a common phrase: "bad bishops defend good pawns".  This means that a bishop might be very bad (same color as all the friendly pawns) but if it is defending them from attack in the endgame, then it might be enough to hold a draw.  Usually it is much harder to win with the bad bishop though.
The other main mitigating factor is if the bishop is defending its own passed pawn or stopping an enemy passed pawn.
Comment: Good info on mitigating factors.
Answer: What you defined is an "inactive bishop". An inactive bishop can be a bad bishop, but they are technically two different situations.
A "bad bishop" is a bishop that is on the same color as it's own center pawns. An "inactive bishop" is one that is blocked by it's own pawns.
Comment: also, fwiw, I never liked the term "bad bishop", it's not bad, it's just in a defensive position instead of an offensive position. In some cases that can be very good.
Comment: So a bishop is bad if it is blocked by the center pawns regardless of whose pawns it is?
Comment: @xaisoft - sorry, I'll edit that, I meant a bad bishop is on the same color as it's own center pawns.
Comment: Good point. I believe I did read somewhere that they "bad bishop" is actually a bad term.
Answer: Several useful answers were given here last year, answers which illuminate the exceptions to the rule so well that—when the answers are read together—they seem almost to leave the rule itself in shadow.  Let me cast my flickering light therefore directly upon the rule.
The good and the bad bishop
The technical adjectives "good" and "bad" have much to do with the worth of a bishop.  A good bishop very often wins a game of chess.  Indeed, unless one has a material lead of two pawns or better, has a passed pawn, or can push or trade pawns to make a bad bishop better, to win an endgame with the bad bishop can be hard.  On my own, limited experience, I should go further:  I would say that to win with the bad bishop, without a strong counter-advantage to compensate so great a disadvantage, were seldom possible absent a gross enemy blunder.
Good against bad bishops in the endgame
Endgames that feature opposing bishops on squares of the same color are quite common in chess, as you undoubtedly know.  As soon as such an endgame seems probable, one might consider pushing as many of one's pawns as possible, on both flanks, as fast as possible, to squares of the color the bishops cannot reach.
In class-D and class-C play, to have pushed pawns in so simple, innocuous-seeming a manner often wins the game 20 or so moves later; insofar as opponents at this level, not grasping the principle, have no idea why you would spend valuable late-middlegame time to push seemingly random pawns.  One, quiet attraction of winning a game in this manner is that it leaves one's opponent with little notion as to why he has lost.  (Indeed, I suspect that it is in large measure because of the mysterious bad-bishop principle that class-D players tend to dislike endgames, why some will launch unsound attacks just to avoid endgames.  They repeatedly lose endgames for no visible reason and don't know why.  All endgame maneuvering, all endgame calculation seems mysteriously futile to them.  The unseen reason, of course, is that they have lost, or at best drawn, before the endgame ever began by letting opponents choose during the middlegame the color of the squares on which endgame pawns must stand.  They think you and your bishop cleverly nimble, hardly realizing how easy it is to be nimble when one's bishop is good.)
Other endgames involving bishops
Endgames that feature opposing bishops on squares of different colors admittedly work on another principle, though such games are significantly less common in practical play.  In bishop-against-knight endgames, which are common enough, however, the square-color principle again emerges, though in a less pure form.
Why the good bishop is good
The good bishop is good for three principal reasons:

because it guards and attacks squares its pawns do not cover;
because it is nimble; and
because its pawns can blockade, and thus fix, opposing pawns on bad squares.

The bad bishop does possess the counter-advantage that it and its pawns can guard one another but, except maybe when the pawn is a rook pawn, such a counter-advantage seldom compensates.
Definitions and remarks
Others have already answered your question about definitions well enough, so here I will add only that I have read the definition as given both with and without reference specifically to central pawns.  When speaking of the opening, I should call a bishop technically bad when central pawns stood on squares of its color, without much reference to flank pawns, as others have noted.  However, from the early middlegame, my view should gradually broaden toward the flanks, eventually taking all pawns into account of the bad bishop.  The two definitions are not unrelated, of course, for the technically bad bishop of the opening is more likely to become the dispositively bad bishop of the endgame than is a technically good bishop, unless its owner either has taken steps to improve it or has swapped it off.
Consider establishing a good bishop when you can.  It may win you some games otherwise drawn or lost.
Comment: You make some interesting points, and I would have upvoted your answer, but you got carried away and waffled a bit too much.
Answer: A "bad" bishop is one that is not performing the normal function of a bishop. That is usually one behind its own pawns. The test is, "if I replaced the bishop with a pawn, would it make any difference?" If the answer is no, then it is a bad bishop.
A Bishop can be behind a wall of pawns and still be very useful. Say there is a bishop on g7 in front of its king on g8, and behind pawns on h6, g5, and f6. As the "linchpin" of the defensive system, the bishop is very useful, even though it has little mobility. (Unless this is a situation where all the action is on the queenside, in which case the bishop would really be "bad.")
Answer: The term itself is rather simple. A "Bad Bishop" is one that is on the same color as most/all ( the higher the percentage, the worse the bishop) and is behind them, that is to say, the pawns are preventing it from attacking the enemy.
If you can get your light-square bishop on the outside of your pawns, it's will no longer be bad, though it may have reduced mobility.
Defensive or not, a bad bishop is bad (the logical end of defensive warfare is surrender - Napoleon) and its bad because it does nothing to limit, or otherwise influence, the actions of the enemy.
Never willingly accept a bad bishop unless you get something in return.
Answer: A bad bishop is one where many of its own pawns are on the same color as it. This definition is very strict, and there's very little subjectivity involved.
An inactive bishop is one that lacks activity. This definition is much less strict, allowing some subjectivity.
As per your question, a bishop trapped by its own pawns would be both bad and inactive, while a bishop trapped by its own pawns would just be inactive (we need info on the color squares of its own pawns to say whether it's "good" or "bad").
It should be noted that a bishop can be "good" and "inactive". Good meaning its own pawns are on the other color complex as it, but inactive since it lacks activity (possibly due to the opponent's pawns blocking it in).
Comment: +1. Finally, a correct answer. I cannot believe the utter garbage above. I want to mention one more kind of bishop that is not good, but not a "bad bishop" necessarily, and that is one, that while it has good scope, it has nothing to attack, while often, the opposing bishop does. That can be a huge advantage.
Answer: Every piece has a strength that depends on the position on the board. More specifically, it depends on the pawn structure and piece placement. As you correctly point out, a bishop trapped behind its own pawns (e.g. white has Bc1, pawns on b4, c3 and d2; black has pawns on b5, c4 and d3) is a bad bishop. In general, a bishop that has almost no available squares and/or no targets to attack is a bad bishop. For example, the rule of placing your pawns on squares that are of the opposite color to the squares that the bishop controls is related to both of these factors. If you have a dark squared bishop and you place your pawns on light squares, two things occur.

Your bishop is not blocked by your own pawns.
Your opponent will place pieces and pawns on the same color as your bishop controls.

Another example of a bad bishop is a bishop that has to support its own pawn chain, e.g. white has Bb3 and pawns on c2 and a4. As soon as the bishop moves, both pawns become unprotected. A bishop needs

Mobility
Responsibility to protect no pawns or only the pawn base (e.g. c2 in a c2-b3-a4 chain).
Targets to attack (e.g. white has Be3 and pawn on a6; black has pawns on a7 and b6; Bxb6 is a constant threat, as well as Be3-f4-b8xa7).

The less these conditions hold true, the worse bishop you get!
Comment: But no positional concept applies in isolation. If your "bad" bishop is holding things together on the Queen-side, while you launch a mating attack on the other wing, he really should not be described as bad, should he?
Answer: One way "bad bishop" can be defined and avoided is by using Capablanca's rule.
1) If you have a bishop keep most of your pawns on the squares of opposite color. This rule has priority.
2) If opponent has a bishop, limit it by using your pawns.
Of course some factors might balance these rules out.
The article below seems to illustrate this very nicely.
It shows how a strong player makes a decision about the "quality" of their bishop and based on that decides on the best structure.
https://www.chess.com/blog/Illingworth/capablancas-rule
Comment: This doesn't appear to answer the question. Additionally, if you post a link answer, you should summarize what's at the link, as links can change or disappear over time.
Comment: Thank you for the comment Herb. Is it ok to edit the answer above?
Answer: Bad bishops and doubled pawns are both commonly misunderstood. The advice to avoid them is usually based on very superficial observations. If you were to focus your efforts on properly understanding them you should gain a class at least. And understanding takes high precedence over defining.
Look at The Secret Life of Bad Bishops by Esben Lund from Quality Chess
Answer: a Bishop is bad if:

it is blocked by its own pawns
the position is closed

On the other hand, it is good when:

it has a wide shooting range (ideally both wings can be targetted at the same time
The position is opened
It is not hindered by its own pawns/pieces


What are the differences between the SR 71 variants?

Question: I read that all SR 71 blackbirds were different, what was different with each one and is one regarded as superior to the rest? Why?
Comment: I'm curious where you read that.
Answer: Like every military aircraft built over the years, the aircraft evolve.  So to address the aircraft's history and all variants, let's refer to it as the Blackbird.
The Blackbird started out as the A-12 procured for the CIA. Fifteen of these were contracted to be built with one being a 2-seat trainer. Two of the 15 were contractually changed to M-21 aircraft prior to delivery.  The M-21 was specifically designed to launch the D-21 drones. The SR-71 at the Intrepid museum (60-6925) in New York was built as an A-12.  One of the M-21's is at the Museum of Flight in Seattle with a D-21B drone.
Three high-speed interceptor prototypes were built and designated as the YF-12A and were capable of carrying 3 air-to-air missiles.  Two crashed and the third is at the National Museum of the AF.
The interceptor was cancelled and the RS-71 program, renamed SR-71 after LBJ's misstatement at the press conference, went forward for the AF.  Twenty-nine SR-71A's were built along with 2 SR-71B trainers.  When one of the trainers was lost in 1968, the surviving aft part of one of the crashed YF-12A's was mated to the front part the SR-71 static test aircraft to create the sole SR-71C.
There's a huge Blackbird community online.  Detail specs and history are available at blackbirds.net and at SR-71 Blackbirds.
The question of which is superior is an opinion, but one can assume that the SR-71's were "better" than the A-12's as they came later building on what was learned from both the A-12 and YF-12A.
Answer: You may be referring to the fact that pilots felt that all Blackbirds seemed to have a distinct personality e.g. 962 was a hangar queen - a real lemon - whereas 972 never let you down.  Blackbirds were virtually a hand built airplane but as to whether each one was different may have just been a matter of opinion.
Answer: There are a few variants of the SR-71 but there is only 1 that was ever used in an active military role.
The YF-12 was the SR-71's initial test airframe. Of the three airframes build tests were carried out by the Air Force and NASA. Notice the nose is slightly different than the eventual production version.

(source)
A twin cockpit instructional SR-71 (SR-71B Serial Number 17956) airframe was built to train the pilots.

(source)
As far as I know the SR-71 only had one airframe variant, the SR-71...

(source)
The airframe was however capable of carrying a wide variety of payloads as dictated by the mission. You can find a nice overview of them here.
Comment: The YF-12 was the interceptor variant built for the USAF, and it was based on the A-12 - the YF-12 was not a development model for the SR-71, it was a completely separate development.  There were three SR-71 variants, the A and B (trainer) and the C was built from a crashed YF-12 and a static SR-71 test rig.
Answer: If you measure them in stealth, max altitude or speed. A-12 comes out on top. (not that stealth ended up mattering as Russians started to hook up computers to their radars and would then be able to spot the A-12s, they were never flown over Russia for that reason.)
If you measure them in surveillance equipment or range, SR-71 would come out on top.
If you measure in armament YF-12 would come out on top.
(image from cia.gov article OXCART vs Blackbird: Do You Know the Difference?)


Sous-vide - What does circulation accomplish?

Question: Sous-vide has been on my radar for a while, but there is no way I am going to spend $500 for a new kitchen toy, nor have I been terribly excited about the do-it-yourself projects that I've seen over the last few years. Now I see a plug-n-play unit that's reasonably priced (not to mention cutely named) dorkfood, so I'm looking at sous-vide again. I notice that many of the more expensive units are "circulators", others are "ovens". Is the circulation just a way to heat water as it passes through the heating unit, or does movement of the water affect the cooking process? If it does have an effect, what is it?
Comment: I would recommend you have a look at the Sansaire Sous Vide Circulator, instead of the dorkfood temperature controller. Though twice the price, it will give you far better control and regularity of the temperature. Preorders at http://sansaire.com/. Full disclosure: I backed the kickstarter, but am otherwise not affiliated with Sansaire.
Comment: Don't be a devil on my shoulder! I have a serious kitchen toy addiction. That does look like a nice unit though. I think for now I'm going to get the Dorkman. If I find that I enjoy it, I'll get the Sansaire sometime down the line, then I'll be able to have two temps going at the same time.
Comment: Sounds like a plan. When I get mine, I will tell you how it fares.
Answer: Since temperature control is so vital to sous vide cooking, the circulation serves to make sure that all of the water is moving and of an even temperature. If you just had a heating element submerged without a circulator, you would get some convection currents, but there would be hot and cold spots in your water bath. If these differences were even just a few degrees, you could end up with proteins not hitting their coagulation temperatures, connective tissues not softening, pectin not broken down, etc. All in all, it would defeat the purpose of this cooking method!
As for the differentiation between "circulators" and "water ovens", there may not be one. Frequently the actual thermal unit and pump is referred to as the "circulator" and the whole assembly with a vessel and water is referred to as the "oven", but I'd check the specs of each model to see whether it has all the parts you're looking for.
Comment: An aquarium bubbler or a small fountain pump would probably work. I think the main risk of hot spots would be with a single submerged heating element. In something like a rice cooker or slow cooker, the risk should be reduced a lot.
Comment: I would use a slow cooker and/or a rice cooker, so while temp might vary slightly from one part of the unit to another, I wouldn't expect dramatic hot spots. I suppose I could look at that with a thermometer before I consider the controller. What do you think of something like an aquarium bubbler to keep the water moving?
Comment: @Jolenealaska Sous-vide in a slow cooker has already been discussed: http://cooking.stackexchange.com/q/32309/1672


Can randomly-generated field names help avoid SPAM bots?

Question: If I were to generate my field names randomly each time a contact form was rendered, would that help prevent SPAM bots from recognizing the fields?  Can they read label text?
Answer: It will help but it won't prevent it from stopping all spam. The changing name fields, assuming they are unique every time the form is displayed, will help stop the bots that depend on knowing the form fields ahead of time to complete the form. It will also help stop the bots that look for exact field names like "name" and "email", etc.
What it won't stop are bots that are smart enough to look for field names that are like common field names but not always exactly the same. They look for fields that contain common field names like "name" and "email". So if your form uses those identifiers inside of your dynamic field names they will still get through. Your idea also won't stop human spammers at all. They'll just fill out the form and submit it without any difficulty at all.
If you want to stop bots, these are some options you can implement along with your dynamic field names:
1) Putting a fake field that only bots will see. Then if that field is submitted with the rest of the form you can ignore it (and ban them if desired). You can also trap bad bots who follow a hidden link.
2) Use a CAPATCHA like reCAPTCHA
3) Use a field that requires the user to answer a question like what is 5 + 3. Any human can answer it but a bot won't know what to do since it is auto-populating fields based on field names. So that field will be either incorrect or missing in which case the submission will be rejected.
4) Use a token and put it into a session and also add it to the form. If the token is not submitted with the form or doesn't match then it is automated and can be ignored.
5) Look for repeated submissions from the same IP address. If your form shouldn't get too many requests but suddenly is it probably is being hit by a bot and you should consider temporarily blocking the IP address.
6) Use Askimet. It is great at identifying spam.
Comment: Thanks John.  What if the field names are completely random alphanumeric strings?  (Such as 8f532GH1.)
Comment: That will stop the bots that look for common field names for sure.
Comment: Also, can the amount of time it takes between the form page being shown and the action page being accessed be a potential check?  (If I'm correct, wouldn't a bot be able to submit instantaneously, where a human would take longer?)
Comment: That is good in theory but it's hard to say how quickly someone can fill out a form. If you keep the timeframe short, say no more then three seconds, then I would *think* you wouldn't affect a human who was submitting a form. Anything that can potentially stop a human from filling out the form is always something that really needs to be thought out as you never want to turn away real users no matter how bad spam gets.
Comment: Thanks again!  I also found your response to: http://webmasters.stackexchange.com/questions/3588/how-do-spambots-work to be really helpful in understanding how they work.
Comment: @Belmonster I'm not sure that would really work. For starters you're gonna need label fields so that users know what information to put where. And on the back end, if the field names are completely random, how are you supposed to know which field is which?


Should a special version of a website be developed for tablet users?

Question: Does the desktop browser version of a web site always suffice for the tablet version(assuming no flash)? or is it common for websites to have a special tablet version that is different from both desktop and phone?
Answer: Websites can be set up in a way that they adapt to the screen size of the device. This is called responsive design, where the design reflows in response to the viewport. This can also be simulated by reducing the width of a browser on a desktop system.
This technique can remove the need to do a separate site version for the purpose. Depending on the need of the site, a full mobile version may be appropriate; in other cases, a responsive design will suffice.
Good articles on the subject:

http://www.alistapart.com/articles/responsive-web-design/
http://coding.smashingmagazine.com/2011/01/12/guidelines-for-responsive-web-design/

Examples of responsive designs: http://mediaqueri.es/
Answer: Tablets (and phones even worse) have smaller screens than do desktops. Text entry is also more difficult because of the clumsy on screen keyboards (which cover even more of the already cramped screen). So you have to carefully design the site to work well on a very limited amount of space and to require minimal text input (dropdown boxes, selection lists, etc. whereever possible).
Answer: Most websites will function adequately on tablets as-is, although you do have to be careful with things like dropdown menus, as there is no concept of "hover" on a tablet.
Many websites actually have a somewhat "better" experience on tablets, because the tablets know how to find the edges of the website and eliminate the unused real-estate (like the white borders you see around this page).
That said, there are many websites that either provide a mobile version of their site (typically auto-detected by the website via the User Agent property of the browser you are using), or give you an app.  On phones, due to the very small screen size, this strategy is essential.
Comment: "Drag and drop" or "sliding" are another examples of a feature that simply doesn't work the same on a tablet like on the PC - mobile browsers scroll the webpage by that gesture instead of letting javascript handle it. (maybe there is a way around that, though, but you would have to take care of that)
Answer: It depends heavily on the website, I've seen some that work great on tablets (and phones) with no special tweaks or extra configuration, and some websites that are completely hideous to use. The only way to ever be sure is to try it yourself or wait until a user mentions it.
A simple rule is if there's any level of complexity to the site you'll probably want to revise your approach to the site's UI to cope with the different level of interaction.


How can I engage my chest more when doing pushups?

Question: I understand that pushups are supposed to be a chest exercise primarily. However, I find that I use my triceps and anterior deltoids more than my chest when doing the exercise. How can I engage my chest more when doing pushups? Do I do it by squeezing the chest in the eccentric portion? Thank you.
Comment: Don't fully extend your triceps but always focus on your chest. Tensing and squeezing your chest but never putting the full weight on your triceps.
Comment: Pushups are not supposed to be a chest exercise, it is a horizontal push exercise, which uses shoulders, triceps and chest muscles together.
Comment: Make sure to retract your scapula while performing the push up. This is the thing that will let you slightly engage your chest more.
Answer: CMK,
I'm assuming you can perform a decent number of push-ups, so it may feel like you are using your triceps and deltoids more than your chest but it may because they are smaller muscles and fatigue quicker than the larger chest muscles. The chest is still doing the majority of the work but here are some techniques you can try.
How To Engage The Chest More Performing Push-Ups
Push Up Technique
Set Up:

Place hands shoulder width apart with the crease between your thumb
and first finger pointing straight ahead.
Screw your hands into the ground to create torque throughout your
arms and shoulders. **to do this imagine holding a barbell and as
hard as possible try to snap the bar in half and pull it apart
simultaneously.*
Keep your elbows about 45 degrees away from your torso, not flared
out up by your shoulders or tucked close to your torso
During the eccentric portion of the push-up think about pulling your
body into the floor and allow your scapula to retract (pulling your
shoulder blades together).
Keep your shoulders over your hands during the entire movement and
keep your forearms in a vertical position, perpendicular to the
floor.
During the concentric phase, continue to keep the torque throughout
your arms and think about pushing your elbows together and squeeze
your chest together.

Push Up Variations To Engage The Chest

Elevate your feet- put your feet on a bench
Elevate an arm- use a medicine ball or yoga block to elevate a single arm, which will result in stressing the opposing arm
Use a slider on one side- keeping a slider on one hand slowly slide one arm directly out the side of the body while performing the eccentric phase of pull up. As you perform the concentric phase pull the arm back into the body
Perform a slow eccentric push-up- lower your body as slow as possible on the eccentric phase of the push, aim for 30 seconds on the eccentric phase and when you hit 0 at the bottom of the movement push up as fast as possible
Perform a plyometric push-up or clapping push up- push up during the concentric phase as fast and explosive as possible, as the hands reach the ground absorb the impact and slowly perform the eccentric phase of the push-up
Answer: Push ups is a complex exercise that engages lots of muscles (it actually engages ALMOST every muscle in your upper body). You won't be able to exclude your triceps and deltoids from involvement in this exercise. But don't hurry up to the gym - neither bench press nor fly would be of any help.
Chest just can't be trained in an isolated manner at all.


Why is noise coming from our hot water radiator even when it is off?

Question: I own a condo and the heating is from a hot water radiator. We have a hot water radiator at the living room and there is quite a noise (some clanking but mostly like water running on a pipe) coming from it even though the main valve is all the way off. The one in the bath and bedroom make no noise on or off. Any tips appreciated.
Answer: It depends partly on your location but many radiator systems have bypass pipes through which water passes to and from other radiators on the same circuit - even it that particular radiator has its valve turned off.

Air in the heating pipework can cause the sort of noises you describe and can be eliminated by bleeding the air from the system.
See answer(s) to similar question
Answer: A clanking noise is often caused thermal expansion/contraction in the pipes feeding the radiators, as the slip in their mounting brackets. That noise can resonate through the pipes for quite some distance, and as @RedGrittyBrick pointed out turning off the radiator may not turn off the loop which feeds it.
The only cure I know for that involves figuring out where the twang is coming from and changing how the pipes are mounted at that point. Which is often more trouble than it's worth.
How recently did you move into the place? Odds are that after a year or two you'll stop hearing the "normal" noises of the place unless you're specifically listening for them.


Intel Nehalem/SB/IB/Haswell CPUs, cache vs TLB

Question: On the Nehalem+ architecture Intel CPUs what is the interaction between the L1 cache, L2 cache, L1 DTLB and L2 DTLB? On all the images I have found there isnt a clear explanation whether the CPU looks at the L1 DTLB first, then goes to the L1D cache, or whether it only goes to the L1 DTLB cache if there is a cache miss in the L1D or the L2 cache?
Comment: I'm not sure you know what a TLB is (Translation Lookaside Buffer, used for caching "virtual addresses to physical address" translations). These have little to do with caches that cache normal data, and if there's a L1D miss it makes no sense to try fetching from L1 DTLB.
Answer: Let's walk through what actually happens when an instruction like mov eax,[ds:ebx*2+4] is executed.
First the CPU has to calculate the virtual address. The virtual address would be ebx*2+4.
Next the CPU adds the segment register's base address to the virtual address to get a linear address. The base address for each segment register is stored in the CPU, and for most segment registers (for most OSs) it's zero, so this can happen fast. Note: There's also some protection checks involved here, but ignore that.
Once the CPU has a linear address it needs to be converted into a physical address (e.g. an actual RAM location). To do this everything is broken up into (4 KiB or possibly larger) pages, and there's several layers of paging structures. For example (long mode), CPU would use the PML4 (Page Map Level 4) to find the PDPT (Page Directory Pointer Table), then use a PDPT entry to find the PD (Page Directory), then use a PD entry to find the PT (Page Table). The page table entry contains the physical address of the page. By adding the "offset within page" from the virtual address to the physical address of the page it gets the final physical address. Note: There's also some protection checks involved at each step here, but ignore that.
All these table lookups take time. To speed it up the CPU caches the "virtual address to physical address" translations (including the final/resulting permissions for protection checks) in the TLB (Translation Look-aside Buffer).
Once the CPU knows the physical address, it can read the data from that physical address. This can be slow too, so the CPU uses other caches to cache the actual data.
Now; the problem with caches is that (due to "technical stuff") the larger they are the slower they are. To get the best performance and larger caches, they have multiple levels of caches - e.g. very small very fast L1, larger/slower L2, etc. For the caches close to the CPU, it can also help to have different caches for instructions and data (different working sets, different access patterns, etc). This is why there's L1I and L1D, then a (unified) L2 and maybe a (unified) L3.
Of course the same applies to TLBs - there can be multiple levels of TLBs and different TLBs for instructions and data (plus some more caches specifically for the high level paging structures to reduce TLB miss overhead).
Getting back to those "virtual address to physical address" translations - if the translation is not cached in the TLB, then the CPU needs to fetch (potentially) lots of tables from RAM to do the translation. A TLB miss causes several fetches, and those fetches might (or might not) be satisfied by data still in the L2 or L3 cache.
Answer: A common method is to access both in parallel. This method is described in the Wikipedia article: http://en.wikipedia.org/wiki/Translation_lookaside_buffer.
The whole point of a lookaside buffer is that the CPU looks there as well as somewhere else, typically using different parts of the same address. Either can miss, and what happens next depends on the architecture.
Comment: CPU can't know physical address until after it converts virtual address into physical address; so doing both at the same time isn't possible.
Comment: @Brendan: Not so. Read the article. TLB is set associative. Page offset bits of the VA and PA are the same.
Comment: Either the Wikipedia page is wrong or you misinterpreted it. It doesn't matter to me which. The idea that you think "set associative" allows the CPU to use the translation (to fetch from physical memory or caches) before it has the result of the translation makes me think you've misinterpreted.
Comment: Ah - I see now. The wikipedia page says parallel where it means "partially overlapping" (up until tag check) and not "entirely parallel".


Rode VideoMic upgrade

Question: I currently have a Rode VideoMic and am looking to upgrade. I am currently looking at the Rode NTG-2 as I can plug it directly into my DSLR as it can power itself. However, after seeing reviews it seems that it is not much different audio quality wise from my VideoMic. I have around £250 to spend on audio so any recommendations would be good (looking specifically for a shotgun but lapel would do). Is the NTG-2 a good step up as nearly all people start off with VideoMic when starting audio but where do you go from there?
Answer: I find my video mic more suitable as the ntg 2. the ntg 2 has less output and is more noisy. Uf you want to upgrade buy the ntg3 and a seperate mixer/recorder an sync afterwards with plural eyes.
Answer: If you really want to up your game audio quality wise, you need to move in to dedicated recorders, or at least a pre-amp or mixer that you feed in to the camera.  This will allow you to use real, good quality professional microphones and greatly improve your sound quality over having to work around the constraints of the mic jack on your DSLR.
Personally, I use a Zoom H4n and record directly to that, but there are also people who take the line output from there and feed it in to the camera's input after going through the necessary pads.

Rode VideoMic upgrade


If a law abolishes a crime, can the law pardon people previously convicted of that crime?

Question: For example, could a law that legalizes a drug retroactively free people previously convicted on charges for that drug so long as they didn't break any other laws? I know laws can't retroactively punish someone, but can they do the reverse?
Comment: related: https://law.stackexchange.com/q/1667/3754
Answer: "The law" cannot offer a pardon, but an executive might. For instance, the governor of a state often has the power to grant pardons for state convictions, therefore a governor can pardon e.g. those convicted on state misdemeanor marijuana possession charges. Such a pardon is not automatic and is not guaranteed, hence in Washington, it took almost 7 years for the governor to offer a procedure for applying for pardon, subsequent to the state's limited legalization in 2012. It can also be done by legislative act (as was done after the governor announced the pardon program), where a law was passed allowing certain people convicted of certain marijuana offenses to apply to the court to have the conviction vacated. A legislature can also pass a law vacating a conviction when the underlying act remains illegal, for example prostitution is still illegal in Washington, but in a specified subset of cases, certain people can have their convictions vacated. In other words, it requires specific executive or legislative action.
Comment: It may be worth noting for OP that, although 'pardon' isn't the right word for it, the result he's asking about can also be brought about through the courts but that, even then, it may not be automatic. On the topic of life sentences without parole for juveniles, the U.S. Supreme Court retroactively applied their decision that such sentences are unconstitutional in a separate case years later. It also did not automatically release prisoners serving those sentences (like a 'pardon' would), but rather allowed them the opportunity to go before the parole board.
Answer: As a general rule assume no

when a law is abolished, the conditions under which previous convictions are to be delt with can be determined, but must not be

In the case of §175 in Germany, no conditions were set

so no further charges, but existing convictions remainded as is

At a later point of time it was desided that the nullification could be applied for.
See the chapter Pardon of the victims in the wiki article

Germany §175 StGB
https://en.wikipedia.org/wiki/Paragraph_175#Pardon_of_the_victims
Answer: Yes
It can and has happened. For example, laws that decriminalized homosexuality usually include a blanket pardon for people convicted under the previous laws.
Comment: Actually citing examples of such law would help.
Comment: Alan Turing most definitely didn't receive a pardon as part of a "blanket pardon". Most likely because it took 50 years for opinions to change from "it's bad, you should go to jail", to "it's bad, but not bad enought you should go to jail", to "it's bad, but not really anyone else's business", and finally fifty years later "who on earth had the stupid idea that being homosexual is bad".
Comment: This isn't always correct.
Comment: @gnasher729 More a change in attitude to "We can turn the gays against the transgender community."


When writing science fiction, how important is it to provide scientific details for the (fictitious) things you are presenting in the story?

Question: I know there is a difference between 'hard' and 'soft' science fiction. But even then, it can be hard to know what sort of categorization in which to place and treat your story, and it is not really clear how little science 'soft science fiction' is allowed to have.
Comment: "how little science 'soft science fiction' is allowed to have" - so, it seems like you are asking "Where sci-fi ends and other genres, like fantasy or paranormal, begin?"
Comment: It is good if you do but much more important to think through the consequences on a society.
Comment: I have absolutely no idea about how a light saber is even remotely possible. But when I first saw the first Star Wars movie when it was new, I loved it because it was so preposterous yet worked perfectly for the movie. I believed it anyway.
Comment: Consider your audience. Do they want a Tom Clancian highly technical thriller? Those people probably exist. But they're a lot fewer than people who don't care about how many tachyons per cubic second it takes to accelerate your ship to 40c.
Answer: You only need to present as much information as is necessary for the plot.
Let's use the classic SF technology, Faster Than Light travel. If all it's doing in terms of the plot is moving the characters from A to B, no further elaboration is necessary. On the other hand, if the method is important, you need to get into it more. To use an example I've read recently, Glynn Stewart's Starship Mage series. There FTL is literally magic; a specially trained mage can cast a spell that teleports a ship no more than a light-year in a single jump. Because it's important to the plot, you quickly learn more about it and the limits; how often a mage can make a jump without their head (literally again) exploding; how the ship has to be prepared for the spell to be cast, details about the special place on the ship where the mage operates, and so on.
Because the series features space battles and pursuits and piracy and boarding actions and all the classic space opera fun, all of that is relevant. You need to know a bit about how the (magic) tech works and its limits to justify why, for instance, the main characters can't simply jump somewhere else when the bad guys show up, or why seizing the ship's sanctum means they can't run, and so on.
Now compare that to, say, Star Wars. You need to make calculations to jump to hyperspace, you can only fight in normal space, and in some places you can't go to hyperspace. That's about it. But in terms of the story, that's all you need to know.
Comment: To attack the "as much as relevant from the plot" thing from another angle -- if the FTL engine never fails, you only need to say "it's an engine that makes you go faster than light." If your main character is the ship's chief engineer and the plot revolves around recovering from a malfunction, you might need to go more in-depth with Bose-Einstein condensate and tachyonic matter and megaluminal accelerationizeifier 9000s. Of course, none of that has to be _real_ --- as long as you keep it consistent and trim what's not relevant.
Comment: Adding to this, Steelheart by Brandon Sanderson uses scientific facts to describe superpowers as a way to enhance the plot, either allowing the characters to mimic powers or expose the limitations and weaknesses of powers. Ex: When a character is invisible, they can't see anything, because they bend light around them but need light to shine into their eyes to see. In this way, scientific facts can actually drive plot, engaging the reader even more by making practical the concepts that seemed meaningless and abstract.
Comment: It's good to point out that the necessity of making calculations is important for the story (causes delay in Falcon Millenium jumping into the hyperspace). Yet to justify Han Solo explains that without calculation you might end up in a star which is something you don't want (writing from memory). Another great example where the way FTL occurs is Dune series, where the whole plot is around gaining control over the substance needed to enable FTL (the spice that exists exclusively on Arrakis and cannot be artificially produced - well, at least in the beginning of the series ;-) ).
Comment: Note that even when details are relevant, characters may focus more on the *effects* than on the scientific theory. Most laymen will probably NOT know the theory, but know that it goes boom if used more than 3 times without cooling.
Comment: This is simply not true for a certain, non-negligible SciFi reader base. Avid readers of e.g. Charles Stross probably care more about the irrelevant technological details than they do about the overarching plot, because that's what they look for in a story.
Answer: You should think about the science in Science Fiction in the same way that you think about everything else in your story:
Is it relevant to the story?

Yes => Include it
No  => Don't include it

In soft SF, worldbuilding and description are subordinate to storytelling. In hard SF, storytelling is a means to transport ideas or facts.
When Arthur C. Clarke wanted to inspire us to build a space elevator, he included all the necessary technical detail in The Fountains of Paradise. When Ann Leckie wanted to make us think about language and gender, she didn't distract us with details of how AIs control human bodies in Ancillary Justice. Clarke has been criticized for his flat, unemotional characters and praised for his vision; Leckie's novel has received acclaim as a character study, but was criticized for its simple ideas.
Answer: Some stories explore the impact of technological discoveries or achievements on society or mankind at large. That could be FTL, a new weapon, a cornucopia, nanotech or simply a space elevator. These stories have tech at their center and need to provide more detail about their characteristics. If we want to explore near-future developments which we consider realistic we must also provide a plausible scientific background and path leading to the technological achievement.
Other stories, by contrast, just use SF as a setting for entertainment or exploration of the human condition; there, technology is just a vehicle for the story and is not at its center in the same way and therefore doesn't need the same level of detail and explanation.
As an example from a different genre consider the role of weapons in a Western. If we are just telling an adventure in a Western setting it's enough to know that you can shoot people with a gun at some distance. If, by contrast, we are telling a story about the impact new weapons like the Winchester rifle or machine gun had on politics, economy and society of the American West in the late 1800s the specific characteristics, means of production, cost etc. of these weapons will be an intrinsic part of the story.
Answer: I believe that in any case of Science-Fiction, you 'need to know' more about the science you are working with than you have to tell in the story. This is mostly to make sure that your fictive stuff makes sense in connection to each other; it abides by the same rules, etc.
Put in other words: The better you understand the tech you've made up, the better you can portray it authentically, be it light-speed travel, teleportation, or anything else.
Comment: Note that the author's "need to know" doesn't necessarily mean you have to understand, or be able to scientifically *explain* your science; however, as @MontyHarder notes, you have to understand the rules of your environment that could impact your story. Also, if in the development of your "bible" you come up with rules you never use - that's OK! you don't have to find a way to squeeze it into the story, if it doesn't belong.
Comment: This is an excellent point, and it might be a better fit for Worldbuilding, but an SF author should write for "internal use only" sort of a "Bible" that sketches out all of the rules that constrain the technology.  You do this to keep yourself honest and maintain consistency.  You only have to actually explain the things that matter to the story (a reader should not ask "why didn't X do A?" when you reveal X did B instead because of a lack of Unobtanium.)
Comment: @MontyHarder and RDFozz - Exactly! Thank you for your comments. Your comments made my answer more adequate.
Answer: You don't necessarily need to provide your justifications to the reader but you should always have a specific and internally consistent justification for how your setting, and its technology, works. Such a framework will keep your story(s) consistent and control any tendency towards supertech runaway where you just throw more tech at problems instead of working within an established set of rules.
As to how much you do tell the reader, that's ultimately up to you but respect your beta readers when they say we need more information or X doesn't make sense, include the information that is directly relevant to the plot and as much more as you feel is warranted.
Answer: To add another twist to the "is it relevant?" answer, consider the tech in any contemporary fiction.
Does it include people driving anywhere? If so, do they describe the internal combustion engine, or even describe the car? If they've got a plane somewhere, how about theory of flight?
Historical fiction, you're more likely to have some description of non-contemporary items. Still, do they describe how to make a candle or a rushlight?
What matters is the purpose it serves. If its behaviour needs to be described for a plot point, then go for it. if there's a car chase scene then the car will always be described, because it matters whether the hero is driving a Lamborghini, or a Ford Focus. But still, what matters is how the car handles, not describing the engine inside it.
Answer: I'd recommend providing as little information as possible. It leaves readers to speculate on how things work and provides you with no limits in the future to what things can or can't do. I'll reference Harry Potter. Use of multiple wands by 1 person, where does the energy come from for spells, limits to how powerful a spell can be, why everyone just doesn't use Avada Kedavra to immediately end fights, why elf magic is so powerful, etc. None of these issues are ever addressed in the books, yet people love to speculate and discuss these issues and the books are huge successes. Then take the Eragon series. The author does a great job of explaining where the energy comes from in magic, explains limits to everything, but the writing gets very detailed and limits what the characters can do in magic since it isn't limitless like in HP. The eragon series is successful, but no where near HP.
It took 10 years to write 7 HP books. 9 years to write 4 Eragon books. It's your world you're writing. You set the rules, not the other way around.
Answer: Issac Asimov, widely regarded as one of the fathers of the science fiction genre, didn't seem to believe details were any more important than you chose to make them. As Ubik has quoted him here: https://scifi.stackexchange.com/a/51327, he chose the term "positronic brain" for little reason more than it sounded cool and futuristic. This is from the author whose novels shaped our collective expectations of robots, and he essentially said "I care more about how robots would affect the world than about how robots work." I feel that's solid advice for a writer: if it doesn't pertain to the subject matter of the work and it isn't blatantly breaking the laws of physics in ways that ruin immersion, then you don't need to bother with it.
Answer: "How important is the science in science fiction?"
It depends upon the audience...If you are writing a hard science fiction story where the protagonist is an engineer who uses her skills to keep her crew mates alive by re-purposing ship board machinery on their crashed ship...You will be explaining or showing why it worked.
However, in most cases do not give in to the temptation to over-explain the science. Most of us know what an internal combustion engine is. However, if you walked around the streets of a typical metropolis and asked passers by to describe the scientific principles, let along the math, that is use in the design and manufacture of that engine, over 95% of respondents could not accurately describe how the engine works. For most drivers, all they need to know is how to operate the thing...not how to design and build it.
Unless the science is critical to the story, most readers do not need to know the "nuts and bolts" of how the science works. Most characters who interact with the technology are users...not maintenance or designers. Show it working and maybe how the character uses it...don't jump out of the story and go into a ten paragraph physics lecture on the scientific principles behind its use.
A way to think about how much detail you will need is to think of driving a car. For most of us, we get inside, fasten the seat belt, insert keys into the ignition, turn it on, press the brake pedal, look around, shift the lever into drive, release the brake pedal, and press the accelerator, turning the wheel to control our directions.
99.9% percent of us, do not think about the interplay between the battery, starting motor, engine, transmission, steering, suspension, tires, and the host of other parts. Unless something is wrong, we are focused on getting where we need to go. Unless something goes wrong, we don't think about all parts and their roles. Likewise, most characters will focus on what's important to them at that moment.
Even mechanical engineers who design cars do not think about the interplay of parts on their drive into work. They are more focused on getting to work. They know about all the science and technology, but that is not what is important at the moment. Focus on what is important and your writing will be better than 95% of the stuff that many authors try to pass off as science fiction.
Comment: If you want someone who actually will both have an understanding of how an internal combustion engine works, and the interactions between various parts of the larger system, ask your friendly neighborhood general aviation piston-engine pilot. In their case, having an understanding of the whole system *as well as* its parts can be crucial.
Answer: Just to add to the other (very good) answers, it's worth pointing out that if your story is from the point of view of an inhabitant of that world, they might not know how a lot of things work.
Imagine a contemporary novel, where someone rides an travellator (a horizontal "escalator"), something that might seem magical to someone from the 18th century.  Does our protagonist know how a travellator works?  Probably not.  They could have a guess perhaps.  But, either way, the novelist doesn't feel the need to explain how it works.
In addition, if the technology is not well understood by you, the writer  (which is inevitable if you're talking about something like wormholes, where nobody really knows how they might work, even their "inventor" Kip Thorne), then the more details you give, the more there is to pick apart and find flaws.  If you just say "Sven took the Cannula and was on Tranquility base within minutes" then the reader's imagination has to do more work.
Comment: It's like you are the only writer here who has characters in your novel…. Or understands what characters are for. +1
Answer: Another reason why you should go as light on the science as you can is to avoid jarring knowledgeable readers.  Suppose you need a faster-than-light drive for your story.  Cool, I have no problem with that.  Now suppose you try to explain it scientifically.  I probably know enough physics to realize why what you said wouldn't work, and that will be unnecessary verbiage that will jar me while reading.
Answer: Good science fiction is good literature.
Therefore, the answer is the same for any literature. Sophistication messes the flow and the flow state of the reader, more importantly. Any sophistication you bring should be worth the high cost just mentioned. One case the answer is obvious: If the sophistication adds to the beauty of the text and the message/meaning of the novel it is definitely worth the cost.


How to send big files via email?

Question: Gmail's maximum attachment size is 25 MB. How to send files bigger than that?
Comment: I am not sure that the problem is only at the send side. Probably also receiving attachments bigger than defined maximum size could be difficult.
Comment: I've often wondered how much data mining some of these random dropbox (not Dropbox®) services do. I know I trust Google and Dropbox claims that their stores are AES encrypted with your password, but I'd look closely at the transfer site you are using if you value your privacy.
Comment: try [http://b2bfiles.net](http://b2bfiles.net) we use it over here at the studio
Comment: I prefer [YouSendIt](https://www.yousendit.com/).
Comment: http://en.wikipedia.org/wiki/Comparison_of_file_hosting_services
Answer: Upload it to a website and send them a link. For example:

Dropbox (in a public or shared folder)
Google Drive
NearlyFreeSpeech (paid)
Amazon S3 (paid)

If you upload it to a public service (e.g. a Dropbox public folder) and it's important that it's kept confidential, encrypt it with 7-Zip.
Comment: Except that drop.io is discontinuing as of December 15th.
Comment: Another website you can use is drop.io
Comment: ifile.it now requires sign up
Comment: Just one more +1 for Dropbox, basically you don't have to worry about resuming partially completed uploads, waiting for the upload to complete etc etc. Just plonk a file in the Drobox folder, Right click the file in Windows Explorer and select Dropbox->Get Link, paste the link in your email and it works!
Comment: Another good and free service is Copy.com, which gives 15GB of free storage (vs 2GB for DropBox).  If you sign up via a recommender link, such as **[my link](http://bit.ly/cloud-copy)**, then you get an extra 5GB free, for a total of **20GB**.
Comment: I use WeTransfer.com all the time. Up to 3gb free.
Answer: since you have an google account already, there is no need to add another hoster for your data: upload the file to docs.google.com as described here and share it.
Comment: +1 Completely agree with akira on this one. You can upload 1GB files to Google Docs even if the file is not a compatible document type. Selective sharing is simple or you can keep it private.
Answer: I've experienced this problem very many times. Thankfully, there are a few good solutions. They all involve using file-sharing services.
Some of the ones I'm about to list have already been mentioned, but I want to compare them in detail.

Hightail (previously YouSendIt) - upload via the website; up to 50MB; not a lot of control in the free plan; paid plans available
Dropbox - somewhat hard to set up (you have to install it once; afterwards, you can just upload via their site); up to 2GB; very private (to view, you have to give someone a username and password)
Comment: Another one: http://www.filemail.com/. Works well - have personally sent up to 350MB files.
Comment: FYI drop.io has been bought by facebook http://blog.drop.io/2010/10/29/an-important-update-on-the-future-of-drop-io/
Comment: Mediafire.com is another simple site for this type of thing.
Comment: drop.io looks ruined. The guy that founded it - Sam Lessin has put up a page like a 10 year old that you get redirected to when going to drop.io. It redirects to http://wlessin.com/ which says "i am sam lessin. I work at facebook. I used to write a lot and stashed my public writing here. I organized Y+30 in New York. I founded drop.io, created letter.ly, csvemail and a bunch of other projects to play with information. I am curious about a great many things."
Answer: 7-Zip also has the ability to save an archive into multiple chunks, and you can specify the size of the chunks.
Comment: Not practical if the recipient does not have 7-zip
Comment: create a selfextracting archive.
Comment: You can't attach exe files in GMail
Comment: rename them to .xyz
Comment: And on the receiver end? Corporate accounts (inboxes) are also frequently limited.
Comment: Also WinRar ( http://www.rarlab.com/download.htm ) have this featute.
Answer: Don't do it.
It is:

Inefficient (MIME encoding bloats the files like 30%)
Insecure
Likely to cause problems for people (ie. you're going to hose your friend's work account who is on Exchange 2003 with a 200MB mailbox that's almost full).

There's just no good reason for file attachments larger than 25MB.
Comment: This is the correct answer to the question. Why did not anybody vote it up?
Comment: Because other answers are providing solutions.
Answer: Try GE.TT
No Flash is required, Easy Transfer of files.
Answer: Lots of players in this space but http://wetransfer.com offers 2GB of space in exchange for your email address.
Its currently flash based only.
Comment: Yes. I like we transfer. However I don't like their new iphone app.
Answer: If you're on a mac I really like CloudApp. Drag the file to the menu bar icon and the URL is automatically copied to your clipboard. Paste it in the email and send.
http://www.getcloudapp.com/
Answer: Sendbigfiles.com Simple and Free!
Answer: Another favorite option is File Apartment at fileapartment.com. Easy to use, fast, no software to download or registration, up to 1 GB, free option, safe, and secure.
Answer: You can try Ipswitch Sendable. There's a free trial that allows you to send up to 250 MB, and paid services with limits of 5GB and 15GB per file / month.
Answer: You can send files up to 2GB at Sprend and it'll also send an email-address notifying where to download the file.
Answer: Upload the file to Rapidshare and send the link (generated by Rapidshare) to the recipient.
Answer: I like DropSend.
Comment: looks like without a "drop" or a "box" in the name of the service one is doome to failure these days. :)
Answer: JustAttach was what we went with.  We could install it on our own servers.  Uses Java for reliable uploads, easy to include links in email.  There is also a product called Repliweb.
Answer: You can split the file using tools like GSplit. But, we still have the pain of uploading. To avoid that trouble, the only way is to host your local PC as a server using tools like HFS. (Google it. I am a new user and unable to add more than a link in a post. Sigh).
Anyway, running server requires some level of configuration and your Internet connection must be quite good to yield proper transfer rate.
Answer: I use http://www.filesharehq.com - free account for sending and storing 500MB and I can use ftp to load files.
Answer: Try wuala.com.  You can share 1G+- off the bat and if you share space in your system 24/7 you can get a proportional amount of space on their cloud for free up to 100G !
Answer: "Microsoft is also leveraging SkyDrive to make it easier to share photos. Users frequently encounter problems with attachment limits either on the sending or receiving side, Mehta said.
Microsoft is skirting around that problem by automatically creating a SkyDrive folder with photos as someone sends an e-mail with photo attachments. Rather than attaching multimegabyte photos with the message, Hotmail will instead send a thumbnail of the photos while the full-size photos are sent to SkyDrive"
Microsoft Rolls out Hotmail Enhancements --> www.pcworld.com/businesscenter/article/196490/microsoft_rolls_out_hotmail_enhancements.html
"Send virtually all the photos you want to without having to worry about attachment limits or clogged inboxes, either at your end or on the recipient's end. Hotmail works with Windows Live SkyDrive, your free online storage space from Windows Live, so you can send up to 200 photos of up to 50 MB each (10 GB total) in a single message.  It's as easy as sending regular attachments, but we give you the option of uploading them to SkyDrive. This means the people you're sending photos to get an email containing a preview of the photos, along with links to launch a slide show or download the photos to their hard drives — all in a single .zip file instead of painstakingly downloading them individually. Or they can even import them straight into Windows Live Photo Gallery. Sharing lots of large photo attachments has never been more easy or painless."
What's new in Hotmail
Answer: There's a few services out there that let you upload a file, and then give you credentials that you can send to people, and then they delete the file after a couple of days.
I used to know most of the players in the space, but it's been too many years -- the only one that I can remember is the one that the company I worked for did (WhaleMail, now owned by Semantic, it looks like)
I have no idea what the current terms / limits / etc are.
Answer: Winrar also has the ability to save an archive into multiple chunks, and you can specify the size of the chunks.
Answer: There is also MyNetworkFolders which provides 1 GB free storage with browser, WebDAV, desktop and iPhone clients.
Answer: I would suggest that the best thing to use would be a file optimization program, such as NXPowerLite. This will remove all the file bloat and leave you with a file size reduction of 60-70% without any difference in look/feel.
Works for me!
Answer: Try FileDropper.  It's a great service.  It's free, the upload max is 5GB, and it's dead simple to use.
Answer: I like http://www.toldacuccot.hu/en — works like YouSendIt.com etc. but without being hassled to start paying. Up to 500Mb per file, and you can send several files at once without having to .zip them beforehand.
If you can arrange to be online at the same time as your recipient, file transfer via Skype is often a quick and easy way to send stuff around, although it quickly gets difficult if there are multiple recipients.
Also, never underestimate the bandwidth of a padded envelope full of DVD-Rs and a stamp.  :o)
Answer: After trying a lot of uploading services, I've finally pick out mediafire.com . It's pretty fast for every country and easy download / upload / share.
You can try http://www.mirrorcreator.com/ to upload to multiple host at the same time.
Answer: You can try TransferBigFiles as described in this article : How to send large files through a website.
All transfers go through HTTPS using SSL encryption.
The free package offers

1 GB Storage
Up to 100 MB per file
Files kept for 5 days
Answer: Sending large files via email is not the best option IMHO.
In fact, there are plenty of services to send large files.
I'm personally in love with FileDropper and Dropbox, but - again - there are lots around. Check here if you want a solid reference:
http://www.masternewmedia.org/how_to_send_large_files_without_email/
Answer: With my customers, I need to receive their stuff: I use Expedimedia.com to Send and receive large files.  It is great because my clients do not have to register.  They also have a free trial account.  Their service is in French and English.
Answer: Here is another good web based service:
LinkAttach
Answer: Google (now) offers Send Google Drive attachments in Gmail:

When you send messages in Gmail, you can attach files from Google
  Drive, such as documents and photos. This is especially helpful if the
  document is larger than the Gmail file size limit, or if you want to
  collaborate with others on the document.
Send a Google Drive attachment

Open Gmail.
Click Compose.
Click Google Drive Google Drive.
Select the files you want to attach.
At the bottom of the page, decide how you want to send the file:

Drive link: This works for any files stored in Drive, including files created using Google Docs, Sheets, Slides, or Forms.
Attachment: This only works for files that weren't created using Google Docs, Sheets, Slides, or Forms.

Click Insert.

Sharing settings for Google Drive files
When you attach a Google Drive file to a message, Gmail checks to see
  if your recipients have access to the file. If they don't, you'll be
  prompted to change the sharing settings of the file before you send
  your message.

Above for 'COMPUTER', there are versions for 'ANDROID' and for 'IPHONE & IPAD'.
Attempt to attach a file larger than 25MB and the following should appear:

so slightly more complicated than a smaller (true) attachment but surely a lot simpler than reliance on other apps (that also take the "via link" approach).

How to send big files via email?


Are questions like "App X is great, are there other apps like it?" appropriate?

Question: If you have some app for something that you like and are looking for other similar apps, is that an appropriate question?
Answer: This is still a list of X question, just rephrased. Consider it as a cooking.se question: 'I like macaroni and cheese, what are some other macaroni and cheese recipes?' It invites poor answers that have a subjective basis (especially here where it would often be localized to a particular handset).
Comment: I agree with your example, but wouldn't the following be acceptable on cooking.se: "I love mac & cheese, but my recipe is missing something.  What would make this better?"  ...I think what our bigger question here is: is this site a place to discover new apps, or do we need to direct those questions elsewhere?
Answer: I'm going to say that this depends on how specific it is.  At the least, it should be community wiki.  If it isn't specific enough, then it should be closed.
Answer: My opinion: If the question specifies how an app would be "like" X, as in providing a list of required features/constraints, then that's OK.
But in that case, you don't really need the "App X" in there.  I suppose it doesn't hurt, but you could just say "I'm looking for an app with these 10 features."
Unless these questions are significantly constrained, there's no appreciable difference between them and What X app should I get? questions.  I'd at least be suspicious of any and all questions taking this format, as they are likely to be treated as polls.


Cognito Forms: uploaded forms

Question: We are using Cognito forms for our scholarship entries. Students are required to upload their resume, essay and transcripts at the time they apply. Sometimes they try to upload their resume as their resume and their essay - for example. I know we can require they upload something - can we require the name of the upload be different?
Answer: I believe the scenario you're describing is possible using some simple calculations. For this example, I'm going to assume that you have three File Upload fields on your form: Resume, Essay, and Transcripts. Additionally, each File Upload field should be limited to one file per field (you can set this limit in the field settings.)
In order to prevent students from uploading two files with the same name:

Add three Calculation fields to your form - one for each File Upload field. Label each field accordingly ("Resume Name", "Essay Name", etc.). Lastly, make sure to set each Calculation field to internal view only.
For each Calculation field, use an expression to target the name of the uploaded file ("resume.docx") in the corresponding field using the Select function. For example, the calculation for the Resume Name field should look like this:
=Resume.Select(Name)
For each File Upload field, select Show Custom Error - When, and set an error to display when the uploaded file name matches either of the file names uploaded in the other two fields. You can do this by targeting the Calculation fields you just created; for example, the custom error expression for the Essay field will look like this:
=(EssayName = ResumeName) or (EssayName = TranscriptsName)
Lastly, make sure to include a custom error message for each File Upload field ("Duplicate file name").

Cognito Forms: uploaded forms


Can I use a 3-way switch as a single-pole switch?

Question: Can I connect a 3 way switch to be used as a single pole?  I accidentally purchased a couple of them and only need to control one light each.
Comment: There was a similar question previously that I'm not finding right now, that question before I believe asked If NEC addressed whether a 3-way switch could be used when only a single pole switch was necessary.   If anyone knows how to find that question please link it.
Comment: I did it today and it worked so rest assured it's possible. I left one of the two brass screws unconnected
Comment: It is legal and possible to use a 3 way switch as a single pole switch just check the listings they are listed as a 3 way dpst or a standard on off spst. Since they are listed as such the NEC section that says must install according to manufacture instructions would eliminate any need to look in the NEC.
Answer: Yes, you can use 3-way (UK: 2-way) as 2-way (UK: 1-way) switches.  It will work fine.  Simply make sure the screws are different colors; you want the common terminal and one of the messengers; not both messengers.
You can do the same with a 4-way (UK: the kind that goes between two 2-ways), again choose screws of different colors, i.e. one from the upstream "side" and one from the downstream "side".  They are not necessarily on the same physical side.
Answer: Yes it can work.  3-way switches are spdt (single pole double throw) with 3 screw terminals, and regular switches are spst (single pole single throw) with 2 screw terminals.
Just pick the correct two contacts and you are good to go.  .
If there are two on one side and just one on the other, then connect to the one that is alone on one side, and either of the other two on the other side.
A multimeter is the quick way to figure out which terminals to use.  Just set it for ohms and you will be able to tell what happens as you toggle the switch.
Comment: Usually the common is black and the travelers are copper. Or silver colored.
Comment: Regarding "If there are two on one side and just one on the other, then connect to the one that is alone on one side, and either of the other two on the other side." This advice does not work in all cases. I have *brand new* switches here where it definitely won't work: one side has a black and a brass screw and the other side has a brass screw. (The screws were correctly installed. I checked with a multimeter.) However, the advice by [Harper](https://diy.stackexchange.com/a/106800/18106) (connect to two screws of different colors) works for every single switch I have in my stock of switches.
Answer: You will have two Common screws. They will be across from  each other on the switch. If you look at the switch it will identify both of them it will say common and there will be an arrow pointing to them. Then above one of the common screws you will have another screw. Wire the hot feed coming in to the common on the same side of the switch as the screw which is above. Then wire the hot feed going to the fixture to that screw  that is on the same side as the common you just wired in. Twist your bear grounds together and hook them to the green screw. The reason this works and is okay is because as a single pole switch has two screws on the same side of the switch. All you're doing is eliminating one of the commons that the traveler would go to. It is not dangerous for this reason.
Answer: Yep! 3-way switches can work just fine as a single-pole. You'll just have a couple of poles open.
Comment: I'm not sure what you mean by "You'll just have a couple poles open", did you mean to say, "you'll just use 2 of the 3 terminals, one terminal will remain unused"?
Comment: While it may be technically correct, the answer doesn't really explain why it's correct and not dangerous to use what is technically the wrong part for the job.  Answers should endeavor to explain they WHY along with the WHAT.
Comment: @Tyson yes, what he means is that is that one of the two hot connectors will go un-used. A "pole" is electrical component jargon i.e. spdt is single pole double throw, google it for more info
Comment: @DanMantyla trust me I know, you missed the hint of sarcasm apparently.