Proving $E_{DFA}$ is decidable by running $A_{DFA}$ several times

Question: I am trying to prove that language $E_{DFA}$ is decidable using multiple executions of $A_{DFA}$ (not using the proof in Sipser's book "Introduction to the Theory of Computation").
Can I just use the given $M$ as a decider?

$M =$ "On input $\langle B,w \rangle$, where $B$ is a DFA and $w$ is
  an empty string ($L(w)=\emptyset$):

Mark the start of the DFA as $q_0$.
Simulate B on input w a finite number of times:

First check if the encoding is correct, if $L(w)=\emptyset$, if not - reject.
Recursively: mark states that can be obtained within a finite $δ$
  operations from any marked states.

If no accept state marked - accept. else, reject."

Is this correct?
Definitions:
$$\begin{align*}
A_{DFA} &= \left\{ \langle B,w \rangle \mid \text{$B$ is a DFA that accepts input string $w$} \right\} \\
E_{DFA} &= \left\{ \langle A \rangle \mid \text{$A$ is a DFA and $L\left(A\right) = \varnothing$} \right\}
\end{align*}$$
Emphasis: I am trying to prove $E_{DFA}$ by running the proof of $A_{DFA}$ several times (finite), so I thought the correct thing would be to use the input $w$ as empty set.
Comment: If the DFA has $n$ states and accepts some word, then it accepts some word of length less than $n$.
Comment: Note you can use `\langle` and `\rangle` instead of `<` and `>`, respectively, and which are *much* better to read.
Comment: would appreciate what is the correct way to do so. i am really unsure above what i've written and it is intriguing me a lot
Comment: I'm not sure what the notation $L(w) = \emptyset$ means. The operator $L$ maps a *DFA* to a *language*. The input is *not* a word. In the text, you mention that you want to use the empty set for the input $w$, but the empty set is not a word.
Answer: If you want to reduce $E_{DFA}$ to $A_{DFA}$, you should use the following theorem:

If a DFA with $n$ states accepts some word, then it accepts some word of length less than $n$.

But a much more efficient algorithm would just run DFS from the initial state, and check whether some accepting state is reachable from it.


Good project management cheat sheet

Question: I see various ones on the web (such at this one), but not being a project manager, I can't really tell which ones are good. I'm looking for a checklist of things to do and important terms; specifically for someone who is new at project management.
Comment: Hi, I'm not sure it's clear what is being asked here.  Can you please edit your question and add more information, such as the **specific problem that you are facing** and what you're looking for.  I'm not sure this is a great question in it's current format as it's pretty vague.  I'm tempted to close it as `not a real question`, but I think the question could be improved.
Answer: I'm not so fond of cheat sheets, as I don't trust in recipes and prefer real thinking. But it can be a good help for a beginner, I think.
The official Project Management for Dummies cheat sheet should be a good beginning, especially if you're not familiar with project management:
http://www.dummies.com/how-to/content/project-management-for-dummies-cheat-sheet.html
Some other cheat sheets:
http://www.thepracticalpm.com/serendipity/index.php?/archives/18-PM-Cheat-Sheet.html
Its step-by-step approach seems interesting and make it immediatly usable for a project.
http://www.focus.com/fyi/human-resources/managers-cheat-sheet-101-common-sense-rules-leaders/
This one has a more transverse approach, things you should know or you should think about all the time, even if I'm not ok with all the points: Is body language really so important for a PM? I'm not so sure...
Answer: This is one I carry around with me all the time: The Project Breathalyzer.
So I beg to disagree that it is only useful for a beginner :-). When you're tied up in project work, it is a healthy habit to sit back at a quiet moment and reflect upon your project. A good checklist can help organise your thoughts.
I found the Breathalyzer through Glen Alleman's site, which is a treasure trove for beginners and experts. One blogpost from Glen is of particular interest for your question: A simple way to put PMBOK to work.
What I also found useful over the years is a copy of Table 3-1. Project Management Process Groups and Knowledge Areas Mapping in the PMBOK. (currently on page 43 in the Fourth Edition).
Update
I actually forgot to mention the most important one, which is my own checklist. It is based upon the Breathalyzer, the PM methodology of the organisation I work for and personal experience. I strongly advise you to start creating your own checklist today (styarting with the examples provided here). It will be a good friend along the way.
Comment: IMO, a "checklist" sounds mutch better than a cheat cheat, and I also advise one, and it should grow/evolve.
Comment: +1 on Alleman!  Call it a cheat sheet or checklist, it is an advisable practice.
Answer: I'm not fond of checklists myself. I think they lead to sloppy thinking. Better understanding the process can lead to using the right tools at the right time. If it's a memory aid for a new methodology, I like it to be a list of questions and prompts. (@david, a checklist is a list of points that need to be checked off. Anything that makes someone think, isn't a checklist).
For instance.
Do you think you've completed initiation? Can you answer the following.
Do you know what you are supposed to be delivering - could you explain it in less than a minute?
Who are your key stakeholders and why are they key?
When is your planning session? Who will be there and why?
I hope that illustrates the idea.
Comment: Pilots and astronauts have used checklists for years.  The concept of checklists has most recently been adopted by physicians and surgical suites doing surgery.  The outcomes are measurably exhibited.  A checklist is both something that is merely checked off as well as something about which you need to think/analyze.  I use one in my verysimpletofly airplane; would not think about leaving earth without it.  The efficacy is simply not debatable.

Good project management cheat sheet


Why is my daughter pulling at her ear when she is eating?

Question: I've read that this can happen during teething, and she is now 4 months.  Thing is, she doesn't have any teeth and isn't really showing the signs in full force yet.  She's not in any discomfort than I can perceive so I doubt it's an ear infection.
She just swats at her ear and sometimes she pushes on it...and it's usually around feeding time.
Ideas?
Answer: Two of my five kids did this, the others pulled or squeezed various other things at different ages. With the ear thing in particular, I think that it is just that the ear/nose/throat are all connected, so they may be feeling some pressure as they swallow and they touch the point where they perceive it.
Kids have weird habits that they get into, then they go away all of the sudden. I'm not a doctor, but... I wouldn't worry about it.
Comment: To worry, or not to worry...this is the question.  :)  Yeah, I'm trying to blow this one off.  It just stinks when they can't talk and you're a clueless parent.  Thanks for the perspective.
Comment: Our kid had an ear infection. But he was not just touching his ears when he was eating.
Answer: Our son did that some times at around that age... the key observation was that when he was doing it during nursing, his ear was at the same level as his mouth or below it. The theory was that he was getting liquid seeping along his sinuses and heading for his ear and he could "hear", or at least feel, it. We adjusted the way he was held while nursing so that his head was more "upright" and the ears were above the mouth and it went away. The main concern we had was his sharp little nails were scratching the area just infront of his ear all up. (Those cutesy little mitten things they sell at the stores in the baby areas... yeah... pretty but useless.)
Comment: I'll pay attention to what position she's in.  The whole sinus connection thing seems plausible, especially since they pretty intensely at that age (sucking every bit of milk). Thanks!
Answer: My sons 8 months old & he tugs & swats at his ears when he is tired. When brought up to his pediatrician he was then examined  for signs of infection but non found. Bringing it up to child's pediatrician to make sure it's nothing serious is a good idea. Every child is different so the meaning of the action of course can be different for other children. For my son it's just a habit especially when he is fighting his sleep.
Comment: The same with our son. And after I observed this at him I realized that unknowingly I do too :-)
Comment: Kids that young see the doctor fairly frequently. Definitely ask when you are visiting your doctor -- even if that is a month from now. Go with your instincts. I think parents are often better at knowing than they give themselves credit for -- if you are concerned -- do something. I suggest keeping a journal. Anything medical gets a different colour -- then you can look back for trends and to see if you've been concerned for a week or ten days. You can journal other stuff, too. Now your child's favourite thing is...
Answer: Myself and my two brothers, according to my parents, all tugged our ears when we were tired.
I actually still find myself doing it once in a while if I'm exhausted and I've caught my niece and nephews exhibiting the same behavior. IMO, it's a telltale sign that they're doneski : T-minus 30 min until complete meltdown; get the story book out or you'll regret it.
This thread at ask.metafilter.com, agrees with all the answers here, including this one. Basically, if they don't have an ear infection or problems with their Eustachian tubes, then they're just tired.
Although their link is dead in that post, a user says: I had always heard that there is a specific "calming" nerve in the ear that helps one to relax when stimulated.
Try it yourself. It feels good, and soon you'll want a nap (you remember naps, right? That thing we all want to do after a large meal ;).
Answer: Maybe she is playing with the sound of chewing. We adults ignore it; but chewing is quite loud for your own ears if you pay attention. By pulling, the sound changes.
You will know when your child have an ear infection, it will be pretty obvious.


Mikvah in Shower

Question: I know there is a way to do Tevilas Ezra( and hence erev yom Kippur Tevilah) in the Shower how is it done?
Comment: Some hold the requisite 9 kav simply come through in the normal course of showering.
Answer: The amount isn't 40 sa'ah, it's only 9 kav.  From an IDF Q&A distributed by ShemaYisrael:

Q. How can a soldier who is on duty fulfill the custom of immersion in a
  mikveh on Erev Yom Kippur?
A. ... The poskim write, however, that one who finds
  immersion difficult can rely on fulfilling his obligation by pouring 9 kavim of water
  on himself (depending upon various halachic opinions, that amount can range from
  between 12.5 to 22 liters of water) in an uninterrupted flow that covers his entire
  body. This is possible by showering.

That means 9 kav is ~3--6 gallons.  Even a low-flow showerhead will use that much water in a 5 minute shower; of course how much of that water wound up on you?  Make it a ten-minute shower and I think you're all set.  I don't think there's any other special procedure, other than making the shower continuous (not turning it off to get the soap or something).
The "9 kav" requirement allows for water that sat in a storage tank, too (unlike the 40-sa'ah-of-fresh-water for a mikvah). Which means the water can be heated.
Comment: I love that I did a Google search for "mikvah 40 sa'ah" and this thread came up as the 4th (and 1st Jewish) hit! Good job, mi.yodeya!!
Comment: @Dave the 9 kav need to be on 'rosho verubo' = head and torso IIRC
Comment: Isn't it required that the water directly hit every part of the body? This doesn't necessarily happen in the course of a standard shower.
Comment: Wait, can the water be hot or it doesn't matter?
Comment: @Jake any temperature, see added piece. 9 kav of "even water that was drawn in a bucket."

Mikvah in Shower


Is there a reaction to get hydrogen from hydrocarbons?

Question: Combustion of hydrocarbons reveals hydrogen, but not sure at what efficiency. Is there a reaction to get hydrogen from hydrocarbons?
Comment: Combustion of hydrocarbons generally does not produce hydrogen because hydrogen itself will combust.
Comment: You could considering cracking. It is an industrial process of getting hydrogen gas. However, the main purpose of cracking is usually to get some light alkene molecules such as ethene from higher petroleum fractions
Answer: Hydrocarbons are in fact the main source of hydrogen gas. According to Wikipedia, 95% of all hydrogen is produced by the steam reforming reaction:
$$\ce{CH4(g) + H2O(g) -> 3H2(g) + CO(g)}$$
This is a very important industrial process which has been studied in depth. It is done at very high temperatures (~1000 °C) and under pressure (~20 atm), and can be "up to 75%
efficient" (though efficiency here may not be defined as solely reaction yield).
As an aside, the fact that so much hydrogen is obtained from methane (itself generally sourced from natural gas, a fossil fuel) is one reason why hydrogen fuel cells currently have limited environmental benefit, though there is a huge amount of research into more efficient techniques for obtaining hydrogen from water splitting (especially using light) which could be carbon-neutral.
Comment: @Shadur Not really. Any plant producing hydrogen is either going to use the CO in some [synthesis reaction](https://en.wikipedia.org/wiki/Syngas), or use it to perform the [water gas shift reaction](https://en.wikipedia.org/wiki/Water-gas_shift_reaction) to produce more hydrogen.
Comment: is there any chance to get C and CO2 instead of CO?
Comment: Downside: Release of a great deal of carbon Monoxide.
Comment: @shadur the reaction mix is cooled, then passed through another reactor where the shift reaction CO + H2O -> CO2 + H2 occurs. After excess H2O has been condensed, the mixture goes to a pressure swing absorbtion (PSA) unit,  where everything except H2 is absorbed onto molecular sieves. Once the sieves are fully charged the pressure is released and all the byproducts are flushed out, and sent to the furnace for burning. They therefore are not wasted but supply part of the heat needed to make the steam reforming reaction go. The PSA normally has 10 or more vessels to enable continuous operation.


When downloading things from TOR, could I accidentally download other random files as well?

Question: So my friend has TOR and he uses it to get some game stuff. But when we went through his files, pictures and videos, we found some files that he claims he never downloaded and they must have piggy backed off his TOR downloads. Now I dont know if he was embarassed by them and used TOR as a scapegoat, or he was serious. I am not a tech kind of guy, and the same goes for my other friends. I'm worried if I use this the same thing might happen to me. I dont want random questionable files showing up in my computer.
Comment: regarding this aspect, Tor is not really different than any other protocol/connection/network/service (like clearweb-pages, email, etc.): it is as easy or hard to accidentally download a file - or files within an archive - you don't want, as it is from any other "normal" site/email/etc. - in this case you can look at Tor as just a different type of connection.
Answer: Tor is a proxy overlay network and is not capable itself of downloading any files on behalf of the user besides the network files associated with the service itself running along with the distributed hash table information that is synced periodically for consensus on the network to allow the onion routing to actually take place.
That being said, other proxy networks like i2p and zeronet are configured so that the user automatically becomes a server and uses a percentage of the users local disk to store content shared to the network of users. Tor is not like these services and does not have that capability in its feature set.
So, your inclination may be correct, they were using Tor as a scapegoat. Another option is that there was a compressed file (like .zip or tar.gz) that, upon download, was expanded to reveal more files than what was supposed to be inside the compressed file.
"Never attribute to malice that which is adequately explained by stupidity, but don't rule out malice either." - Hanlon's Razor
Answer: It is technically possible to download other stuffs but not by TOR itself. I mean TOR is using three router to connect the client to the destination server and if the connection is not secure, the third router (exit node) technically can intercept your connection and inject data to the download stream. But this is very risky method and I do not think any exit node does such thing.
Another possibility is the download site itself. If the download site is some kind of torrent site or warez site, it is possible to add extra downloads to the main download, no matter what browser is used. Hope it helped.


Why does Robb Stark need ships to get to King's Landing?

Question: I am watching Game of Thrones, and I am confused that Robb Stark needs to ask for ships from the Greyjoys. Isn't it all land between the North and King's Landing? It isn't like Stannis' position where there is a large bay separating him from the capital.
Comment: Some more detail would be nice. I don't recall any Greyjoys in the first season except Theon.
Comment: Second season. Robb Stark (against his mother's advise) sent Theon to his father to get ships
Comment: And the reason they give is that Robb needs ships to get to King's Landing?
Comment: something like that, yes. As Beofett says, more precisely Robb wants to defeat the Lannisters in the King's Landing
Answer: He doesn't need to get to King's Landing.  He needs to capture King's Landing.
King's Landing has very strong walls, and the most vulnerable point is the harbor.  However, Joffrey commands a fairly strong fleet.
Robb needs a fleet to take advantage of the best angle of approach.  The Iron Islanders have a very strong naval force.
The plan is for Robb to lead his armies by land to King's Landing, and then coordinate their attack with the Iron Islanders' fleet attacking the harbor.
Edit:
After re-reading A Clash of Kings, the correct answer is more that Robb hopes to have the Ironborn fleet attack the Lannisters directly, striking at their home in Lannisport.
Robb and his armies would march across the land to King's Landing.  However, in the meantime the Ironborn would sail towards Lannisport, the seat of Lannister power, and attack it from sea.
If the attack succeeds, it would be a crippling blow to the Lannisters.  Even if it failed, it would prevent Lord Tywin from committing more Lannister forces to King's Landing, making it much easier for Robb's armies to storm the town.

"By now Robb is at the Golden Tooth," Theon said. "Once it falls, he'll be through the hills in a day. Lord
  Tywin's host is at Harrenhal, cut off from the west. The Kingslayer is a captive at Riverrun. Only Ser
  Stafford Lannister and the raw green levies he's been gathering remain to oppose Robb in the west. Ser
  Stafford will put himself between Robb's army and Lannisport, which means the city will be undefended
  when we descend on it by sea. If the gods are with us, even Casterly Rock itself may fall before the
  Lannisters so much as realize that we are upon them."
Comment: @Curious Yes, it is, but this is a continental war. Robb needs to command the sea because not doing so would allow reinforcements to Kings Landing OR allow Joffrey's fleet to send troops behind Robb and either harass the attacking army from behind and/or attack Robb's assets from behind. Blockading the port would also prohibit enemy supply lines and allow rapid re-supplying of Robb's forces. Furthermore, it doesn't hurt that ships can participate in barraging land assets.
Comment: I see. Anyway, aren't Iron Islands and King's Landing in the opposite sides of the continent?
Answer: This is explained more thoroughly in the Clash of Kings book.

 Theon was sent by Robb Stark to Pyke (the Iron Islands) to have Balon Greyjoy (Theon's father) attack Casterly Rock (the Lannisters' City), on the west side of Westeros, from the sea, while Robb's forces attack them from Land. In return, Robb would have given Balon back his Crown as King of the Iron Islands. Balon was made to bend the knee (by Ned Stark) and give up his crown some years before, after the Iron Islands rebelled against King Robert.
 The idea was to hit the Lannisters at their home, and weaken them, and then with Renly, close in on Tywin's forces from north and south.

So it has nothing to do directly with King's Landing (which is on the east of Westeros)
Answer: I've not seen season 2 yet, it will not air here until May. I think you should fill out your question with more detail, as it is not easy to understand the context here, seeing as the books and the TV-show differ somewhat.
Here's my reasoning that comes from knowing only the books:
Robb has White Harbour, which from what I understand is a great sea power on the east coast. If Robb wanted to get to King's Landing, I doubt very much he would send to Balon Greyjoy, as he would need to sail halfway across the world just to get there. Especially when White Harbour is much closer, and the allegiance of White Harbour is much less questionable.
However, the Lannisters have the Redwyne fleet, which reputedly is the strongest in Westeros. I believe Stannis also controls a major part of the crown's fleet, which sits off Dragonstone. Robb has White Harbour, which probably is the least of those fleets.
However, he holds the trump card: Theon Greyjoy. With Theon, he can secure a fleet that is among the strongest in Westeros. With such a fleet, he can keep the Redwyne fleet occupied in the west, taking pressure off White Harbour's fleet. Controlling the seas is of crucial importance in the war.
And besides that, securing the alliance of the Iron Islands is nothing to sneeze at. They are a martial and hardy people who make for bad enemies. What's more, Robb considers Theon his friend and ally, and by extension probably considers the Ironborn his allies (we don't know exactly what Robb thinks, since he has no POVs).
Re-reading AGOT recently, I read an exchange in a very early Ned chapter, where he tells Catelyn to tell Robb to strengthen Moat Cailin and keep a closer watch on Theon Greyjoy (for this very reason).
Comment: @DanRay You forget the Battle of the Blackwater rush, which is slightly spoilerific here.
Comment: "I believe Stannis also controls a major part of the crown's fleet, which sits off Dragonstone." -- Not as I recall it. He has to hire himself a fleet of Lyseni ships with the help of Salladhor Saan.
Answer: Robb wants the Iron Fleet so he can directly attack Lannisport, (just like Victarion did during the Greyjoy Rebellion.)  Raiding the port just a day or two's march from Casterly Rock would force Tywin's hand, especially with Robb's continuing march west.  He does not wish to attack King's Landing.
Answer: King's Landing is on the east of the continent whereas the Greyjoy ships are on the north-west. The only help they could provide is by attacking Casterly Rock in the far west (the Lannisters' home).
It makes sense that Robb would turn west against the Lannisters if he is able to take out Tywin's current forces in the Riverlands, leaving Renly to go east and take King's Landing and having to deal with Stannis who is even further east.


What vegan food or drink helps to cool off after spicy food?

Question: When people eat something that's too spicy and they want to relieve the heat, one thing that's common to drink is full-fat milk or cream. What would be a good dairy-free, vegan alternative food or drink that helps to soothe the mouth after eating very spicy food?
Answer: The reason for suggesting milk or cream is that capsaicin, the irritant in chillies, is soluble in fat, not in water. Thus, you can put some cooling cashew/coconut/soya/almond (etc) cream/yogurt/mylk (etc) in your mouth and it will work just as well as dairy, as long as it has a reasonable fat content. I quite often serve some kind of dairy-free yogurt-based or tofu & oil-based  or cashew-based sauce/dip with spicy food.
However, I find a mouthful of absorbent, starchy carbohydrate food, such as rice or bread, is at least as effective as creamy liquid and possibly more so. I haven't found any particular scientific reason for this method's efficacy; my assumption is that the food simply absorbs some of the liquid containing capsaicin from your mouth. If I'm eating spicy food with someone (often a child) who seems to be suffering, I always suggest trying this technique (which is generally convenient since spicy food is usually served with carbs like rice and bread) and they've always agreed that it works (though it's possible they're just being polite).
Answer: Anything with a good fat content should work. Avocado, peanut butter, tahini, coconut cream, soy/rice/almond/cashew milk are all items I've used for this purpose.
Answer: Rice. It's very common in East Asian countries (e.g., Japan and Korea) to serve plain white rice with a meal, especially with spicy dishes.
Coconut milk is also often added to dishes in South East Asia to reduce the heat.
Answer: Eat a fruit that has a sour taste (like oranges or a few drops of lime), it immediately reduces the heat in your mouth.
Answer: Some plain white rice or bread/chapati would do very good. You can also eat some biscuits.
Note: Just-in- case you would like to consider/recommend to others, these are some very effective dairy options:

A glass of buttermilk: gives instant relief: contains very little fat
White rice mixed with curd and a little salt for taste
Steaming white rice with cow ghee (refined butter), with some salt and lemon juice for taste.
Comment: Hi there, welcome to Vegetarianism SE. The question specifically asks for **vegan**  options so most of your answer, as it currently stands, is irrelevant.
Comment: Thanks. I have edited it so that it's more relevant.


What is the difference between frijoles and habichuelas?

Question: My understanding is that they both refer to "beans." But there are several types of beans. For instance, there are round, "starchy" kidney type beans. And there are long, stringy "green" beans. Could "frijoles" refer to one type of beans and "habichuelas" the other type? How do you tell the difference between them, and maybe "third" types of beans?
Comment: It is wierd how languages and idioms evolve because in Dominican Republic we pronounce Guandules like Gwandules and Puerto Ricans pronounce it like Gandules...
The word is spelled like Puerto Ricans pronounce it so we are wrong...
DaDominikan
Answer: Given the great extension of territories where Spanish is spoken, there are for a single type of food, many ways to name it, according to the country (or region in a single one).
There's also an opposite case: the same word refers, in two regions, to different varieties of the same food, or even to two different ones.
For your specific question:
Frijol:
This is how in México is called many varietis of Phaseolus vulgaris:

But, as I've already said, this food is called with these different ways:

In Chile (my own country), and Argentina: poroto.
In Perú: frejol (o fréjol).
In Spain: judía.
In Venezuela: caraota negra to the black variation of this food.
In Puerto Rico: frijol only to the black ones; habichuela to all the other ones.

Habichuela:
According to what I've found, in most places habichuela is called the same Phaseoulus vulgaris, but when served green, inside its pod.

In Chile it's called poroto verde.
Comment: I would add:  **ejote** for habichuela, and would comment that in Venezuela (I think) they pronounce frijol like *fríjol* with the strength of voice in the ¨i¨ instead as the ¨o¨ as would be normal pronunciation.
Comment: In Mexico the white ones are "alubias" and the brown ones are "frijoles bayos". And here we say "ejote" for "habichuela" as chapelo said.
Comment: also "judías", this is really similar to the case "guisantes" and "chicharos" also, did you know that the "mexican Lemon" is actually a lime, but if you ask for a "lima" in mexico no one will know what you are asking for.

I mention this because when it comes to different variety of plants different translation arrive, that's because of the mixture of the understanding of what's one thing and what's the other
Answer: "Frijol" is not a common word in Spain, where we use mostly "judía" (also "haba" or "alubia" depending on zones).
In this context, "habichuela" is the long, green pod (containing small beans):

While "judía" (and its american synonym "frijol") is the single bean:

There is a wide variety of both pods and beans, in size, shape and colour.
Comment: En Cuba le decimos judía al frijol blanco http://www.pepekitchen.com/articulo/judias-con-salsa-de-tomate-y-verduras-receta-griega/
Answer: Lots of good answers here, so I'm not trying to outdo anyone (especially since I am not a native speaker of Spanish).  What with so many different names for beans, though, I really started getting confused about what name for bean was used where.  More importantly, I thought it would be helpful to you, myself, and others reading this post, if I could find a way to figure out which ones would be most useful to learn.
Clearly, if you know you'll be visiting a certain region then you'll want to focus on vocabulary particular to that region, but for the vast majority of us who won't be traveling to foreign lands and simply want to be able to take our Spanish to the next level, I thought it might be useful to rank these various beans on what their frequency is in online Spanish newspapers.  So, I took all (or nearly all) of the bean names listed in this thread and then also the ones listed in
Phaseolus vulgaris
(Big thank you to Nicolás for including it in his answer, otherwise I might not have ever visited it.)
I then filtered for language (Spanish) and type of page (News).  I made sure to set the query up to return results for both singular and plural forms (though you will just see the singular listed in the charts below) and added other measures to ensure that what was returned were pages about beans and not something else.  It wasn't an exact science and, for at least one word (blanquillos*), I had to fiddle with the query a bit to make it work, but, if you don't want to learn the nearly three dozen names for beans that you will see between this thread and the Wikipedia article I referenced, and just want to focus on those you might see as you start getting to a point where you can read Spanish news articles, the charts below might help.

*If you type in "bean" into any online English-Spanish dictionary/translator, I doubt any of them will list "bean" for "blanquillo."  Term Bank did not and neither did WordReference.  But since the Wikipedia article mentioned that "blanquillos" was, indeed, the name for beans in Colombia, I did my best to find some evidence that "blanquillo" is used as a word for "bean," and was able to do so.  To back up a bit, Term Bank does list some meanings for "blanquillo."  Among many other things, it lists "small fish" (in Chile) and "chicken egg" (in several others).  Despite the fact that Term Bank mentions it is little used as "chicken egg," I saw several images of eggs surface in my search for "blanquillo."  Most of the initial images were of fish, but I'd have to say that the second most popular image was that of what appeared to be chicken eggs.  Regardless of how frequently people use it for that, I was also able to find at least one image of it as a product that might be sold in a supermarket (other than an egg ... or a fish).  Here it is:

Here you can see that "blanquillo" is prefaced by "frijol," but it appears that this type of bean is often simply referred to as "(los) blanquillos."  Take note of the print at the bottom and you'll see that the product uses a Colombian address on its packaging, which corresponds with the information included for this type of bean in the Wikipedia article mentioned.

As for the rest of the beans, I tried to use an image of the bean that was most representative.  If the word was just a generic name for the bean, I used a generic image (the sacks of beans).  I know that some generic words for beans sometimes refer to a specific variety of bean in certain regions.  For example, Javier above mentions that in Puerto Rico, they used "frijoles" to refer to "black-eyed peas."  So, please keep that in mind as you look at the charts.

The word "haba" is a bit different than the other beans in the chart above.  In the Spanish Mediterranean, "haba" is used for the Vicia faba, which you may know better as the broad bean, fava bean, or even lima bean (habas verdes).  Although technically, the lima bean's actual Latin name is Phaseolus lunatus, which makes it a different species of plant altogether, but still in the same family (Fabaceae) as the "haba."  In colloquial usage there may be some overlap in naming conventions for these different types of beans.
Perhaps the main difference is that the one (the "haba") originated in North Africa and the other — the one English speakers call a lima bean (or a butter bean) and that Spanish speakers might refer to as a "pallar," a "guaracaro" in Venezuela, a "garrofón" in Spain, or simply "frijol" or "haba" (de lima) elsewhere — originated in South America.  They look very similar, so it is not surprising that they are mistaken for one another, but they differ somewhat in appearance, taste, and composition.  From personal observation, I notice that the lima bean tends to have a grainier appearance than the fava (or broad bean).  Below is a side-by-side chart of the lima bean and fava bean so that you can see how similar they look:

From a nutritional perspective, a cup of lima beans will give you, cup for cup, less fat and almost twice as much potassium, but fava beans will give you more protein, more calories (and quite a bit more fat), if data collected from this source is correct.  (Data for lima beans collected here; data for fava beans collected here.)  I put some of the data in a chart so that you can compare them yourself:
I've never had a fava bean, so I can't describe that to you, but a couple of people do so in this thread here: "What is the difference between fava beans and lima beans?
In the rest of the Spanish-speaking world the "haba" is usually just a common dry bean and though you might not see it paired with "blanca," it is paired with "negra" (for "black bean") or "roja" (for "red bean").  Keep in mind that the other names for bean listed previously are far more commonly used and paired with descriptions of color to differentiate specific types of a dry bean.  The word "haba" is also known by many as the word to use for "coffee bean," but there are others.  More on that later at the end of this answer.

As you may have noticed, where I could fit them in, I also added product images.  There's nothing quite like seeing actual merchandise to help remember a foreign word for something.  I can't buy everyone a plane ticket to every Spanish-speaking country in the world, but this is the next best thing.
I did not include four words found in the Wikipedia article — calbotes, balas, balines, and ejotes.  I just couldn't find strong enough evidence linking the first word — calbotes — to the word "beans," despite the article's claims that "calbotes" is the word for beans in Navarra and Tierra Estella (regions in northern Spain).  Both "balas" and "balines," words claimed to be used in Honduras by the aforementioned Wikipedia article, just seemed too difficult to try to dig out from all the pages where these mean "bullets" or "pellets."  Leaving "ejotes" off the list was simply an omission of error.  If you are interested in reading articles from news outlets in Guatemala, Honduras, and Mexico, you will likely come across "elote" from time to time, especially if you read a section devoted to food.  This word for bean refers specifically to "green bean," and had I included it, it would have fallen between "chaucha" and "pocha" in terms of prevalence found in online news articles.  In other words, it appears to be more prevalent than "chaucha" (another term for "green bean") and "pocha" (a different type of bean) and would mean that were it not somewhat exclusive to the three countries already mentioned it might be considered the most universally recognized word for "green bean."  But as it is, I believe "judía verde" or simply "judía" is the word most Spanish speakers (and students of Spanish) are most familiar with for the vegetable we refer to as a "green bean."
The last thing I want to mention in this post (and I'm rather shocked it wasn't brought up yet ... ) is what word for bean should you use when you want to say "coffee bean?"  Reverso seems to prefer "grano de café" as does WordReference.  You'll find that and more (including the previously mentioned "haba") if you search for "coffee bean" with Term Bank.

Source Notes: Nothing other than what has already been given, except for attribution for the image of the caparrones that was used in the second chart above.  Attribution is as follows:
De Xufanc - III 2011, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=14790785
As for the other images, I did my best to make sure they didn't have a copyright on them and/or weren't produced for the purpose of attempting to make some sort of profit off of them.  That is to say, I attempted to preserve intellectual property rights and avoid encroaching upon someone's interest in obtaining compensation for their creativity, talent, or efforts.
Answer: If your a Caribean hispanic from Cuba, Dominican Republic and Puerto Rico we say habichuelas.  Frijoles is used more by individuals from South America, just like cake Caribean hispanics say "bizcocho", they use "pastel" which means a different food for us.  Also "bizcocho" in some South American countries can mean a vulgar way of saying a women has a hairy vagina.
Answer: From what I know (since I am Spanish, been living there all my life), all the above are used unanimously. But mostly they are used like the following:

Judías Verdes: String beans
Judías Blancas: Butter Beans
Judías Rojas: kidney beans
Judías Mungo: Moong beans

I hope my answer serves you well.
Thanks.
Answer: In Colombia frijol is used when referring to dried red kidney beans,  while habichuela refers to the green version of beans.  Frijol is the raw material for feijoada, bandeja paisa and other custom - Americanized versions of Spain's favada.  Frijoles are soaked then slowly cooked with pork and served with rice, plantain, more pork, and whatever is related to local preferences.
On the other hand, habichuela is not really tasty.  It doesn't belong to a specific dish,  instead it is used in mom's cuisine as a versatile, cheap and convenient ingredient to make stews with meat or poultry.  We are not fans of habichuelas.  They are like grandma's food when you're in the dog house.  Instead we love frijoles.
Answer: The way I remember it in Puerto Rico we called all beans "habichuelas" with the exception of black eye peas which we called "frijoles" and green beans which we called "habichuelas nuevas".
Answer: Judías o habichuelas se usa en España.
Frijoles se usa en América.
Las judías verdes o habichuelas verdes son las vainas tiernas comestibles de la planta. En partes de Centroamérica, por el náhuatl ¨exotl¨, le decimos ejote.
En partes de América pronuncian frijol, con el acento en la "i", pero no sé por qué razón.
Answer: En Puerto Rico tanto a las habichuelas como a los frijoles tambien le decimos Granos. Generalmente le decimos frijoles solo a las negras. Al resto, habichuelas. A las verdes en su vaina le decimos tiernas.
Answer: In Mexico Frijoles are the Dry Beans. While Habichuelas are the green ones.
Answer: Just a note about Spain's terminology:

judía can be the plant, the pod or the bean. A Google Images search makes me think "pod" is the most usual meaning.
habichuela can also be the plant, the pod or the bean. A Google Images search seems to show that it is used for both pod and beans.
alubia can also be (you guessed it) the plant, the pod or the bean, at least technically; though it is used most often for the beans (Google Images search).

The above three can be more or less synonyms, depending on the Spanish region. In my area judía means the plant or the pod, and the beans are called habichuelas. In some other areas it may be exactly the contrary (as inferred from the existing answers).
I say this just to make clear that current "in Spain" answers do not necessarily apply to all of Spain. Don't be surprised if you ask for habichuelas con jamón and get served this in some places and this in some others :D
On the other hand,

haba is used specifically for the broad bean (plant, pod or beans -- Google Images search).

And finally:

bajoca is used in south-eastern Spain to refer to the green pod variety (it is a Catalan word, so it is probably used in all of eastern Spain too).
Comment: [**WordReference**](http://www.wordreference.com/es/en/translation.asp?spen=habichuela) supports what your link to [**the DRAE entry for "habichuela"**](http://dle.rae.es/?id=JvBitQl) gives us in Spanish and what you've observed through images.  Thanks for the links to the image searches.  I find this type of searching useful and use it myself quite often.


Introductory References for Geometric Representation Theory

Question: Would anyone be able to recommend text books that give an introduction to Geometric Representation Theory and survey papers that give an outline of the work that has been done in the field? I'm looking for references that would be suitable as a follow up to James Humphrey's "Linear Algebraic Groups" and a first year graduate Algebraic Geometry course. I'd also prefer the texts to be in English but if it's necessary, I could also read references in French.
Answer: I would encourage you to consider "Representation Theory and Complex Geometry" by Chriss and Ginzburg. In particular, I think you might enjoy the realization of irreducible representations of the Weyl group of a complex semisimple group $G$ on the Borel-Moore homology of the fibres of the Springer resolution of the nilpotent cone. For me, this has always been one of the motivating examples in geometric representation theory.
Comment: Thank you for the reference. I've checked out a copy of the book and it looks interesting, particularly the part you mentioned.
Answer: Additionally to Peter Crooks answer I would recommend to study the book of Hotta and others :
D-Modules, Perverse Sheaves, and Representation Theory
Here you can learn about derived categories and perverse sheaves/d-modules (which are essential tools to study geometric representation theory) and how they are connected to representation theory.
From here on it is not far to understand the geometry involved
  in the context of Kazhdan-Lusztig theory, Koszul Duality (in the sense of Beillinson, Ginzburg and Soergel), the Geometric Satake equivalence (Mirkovic-Vilonen).
Comment: Thank you. I've been looking particularly for a reference for perverse sheaves and D-Modules. I will check this book out.
Answer: I am currently reading though the two books already mentioned (Representation Theory and Complex Geometry by Chriss and Ginzburg and D-Modules, Perverse Sheaves, and Representation Theory by Hotta et al) and I definitely recommend them. Two other references  that I have found helpful are:

Fulton's Young Tableaux. This presents a snapshot of the geometry associated to $ GL_n $ (e.g. producing irreducible representations from lines bundles on flag varieties). It is also a relatively easy read!
Humphreys' Representations of Semisimple Lie Algebras in the BGG Category $\mathcal{O}$. Whilst this is not so much about the geometric side of the picture, what I got out of it is an appreciation of the types of questions people in this area try to answer.
Comment: I have been using Humphreys' book recently because there's a course at UC Berkeley I'm taking which is currently going through the BGG resolution and Beilinson-Bernstein and Humphreys' text is the only one I've found which gives a good construction of the former.
Thanks for the Fulton reference. I wouldn't have thought to look through that judging by the title alone.


40 page troll patent by Magna Electronics citing 1795 sources

Question: I found a strange patent - it is a US 9014966 patent called "Driver assist system for vehicle" by Magna Electronics (the biggest car part supplier in the world). The patent was applied for in 2000 and was granted in 2014, 14 years later. It has about 40 pages, very few illustrations and in my opinion "over-specifies" (lists lots of claims without proving they actually are needed for the "function"). Is this a troll patent?
Answer: The priority date is in 2000 - it was filed in 2014. It is likely to expire in 2020. IMO it does not appear to be a "troll patent". Also the Non-patent citations are only 29.


Why do stomata close in low intensity light?

Question: Stomata close during high intensity light to prevent excessive transpiration but why did they close during low intensity of light? Please explain in easy- understand language because i'm  in just 10th standard.
Comment: Think closed state as default state, it is the light which opens the stomata, So in the absence of light stomata go backs default(closed or resting or inactive) state.
Comment: Do you have a source in support of your assertion that high light intensity causes stomata to close?
Answer: The primary function of open stomata is to promote gas exchange in leaf tissue: atmospheric carbon dioxide is a substrate for photosynthesis. A side effect of opening the stomata is an increase of water loss through transpiration. If light intensity is low then photosynthesis will be depressed: under these conditions it makes sense to close the stomata to conserve water.


Why didn't T-Rex and Velociraptor attack each other?

Question: In Jurassic World, after defeating the Indominus Rex, the T-Rex and Velociraptor exchange a glance and then leave different ways. Was that really a natural behavior?
Comment: It's actually impossible to determine how t-rex and raptor would actually behave, all we know is that despite living millions of years apart, they were both carnivorous and the sight of each other would have most certainly ended up in a fight, however for the benefit of the film, I think that rexy sustained far to much injury from the battle between itself and the indominus Rex that it quite frankly couldn't be bothered. Second to that, my question is where do they go from here in terms of the next film? I think they should turn it up a few notches, make it far more blood thirsty, numerous rap
Comment: well blue helped rexy to kill the indominus just because the indominus injured her pack mates.
Answer: I think it was just a way of showing the (albeit temporary) bond that they developed during the fight. Don't think the writers meant for the audience to read much into it.
T-Rex : "Dude, thanks for helping me out there. High five. Now get the hell out of my face; I've had enough shit for one day"
Velociraptor : "See ya around big guy" * zips away *
Comment: I think another way to phrase it would be similar to a bar fight. Teaming up with a complete stranger because of a common goal, then parting ways on a tenuous (and temporary) truce. Some of these dinosaurs were allegedly quite intelligent, so it is not unreasonable to assume that their proto-bird intellect could come to such a conclusion.
Answer: I did some checking after my comment and found that T-Rex (fossils are found in a variety of rock formations dating to the Maastrichtian age of the upper Cretaceous Period, 68 to 66 million years ago, wiki) and Velociraptors (lived approximately 75 to 71 million years ago during the later part of the Cretaceous Period, wiki again) did not lived on the same period of time.
Also a T-Rex has a speed of roughly 18mph while a Velociraptor run up to roughly 40 mph (too fast for a T-Rex, wiki), and Velociraptors hunt in packs (specified in the movie).
Now referring to the movie T-Rex sees Indominus Rex they growl, no one backs up so they both attack (natural behavior to me). The Velociraptor follows Owens command and also attacks. After that fight there is no reason to fight each other, none of them display aggressive behavior towards the other.
Comment: Why would them not having lived in the same period of time have to do with them not attacking one another? Their species may not have lived in the same period of time, but we're talking about dinosaurs cloned from blood found in mosquitos entombed in amber. The T-Rex and the Velociraptor have no concept of "their time", only their current time, the here and now.
Comment: The title is `Why didn't T-Rex and Velociraptor attack each other?` The question is `Was that really a natural behavior?` . I tried to explain at the beginning that those 2 had not encountered before to know their natural behavior. And if you would have red the whole answer the last paragraph tries to logically explain their behavior.
Comment: Right, and if this were either of thier periods of time that would be a valid point. As it stands, though, they're living in the same period, so it's not really a valid point to be made because neither of them knows they never lived in the same epoch millions of years ago.
Comment: You are right, but if they had lived in the same period then perhaps their encounters would have been documented (T-Rex fossils with Velociraptors bite marks or the other way around) so my supposition would mean nothing.
Answer: Considering these are not real T-Rex or Raptors (in universe, states to have been manipulated to fit the public imagination of what dinosaurs should look like), not knowing how much they are manipulated, them not being natural competitors due to time periods, etc, the simplest answer is that we can't tell.
Now ignoring that, we can guess based on modern day animal behavior. There are many animals, prey, predators, or even apex predators that will occasionally team up for various reasons. Even ones that will normally be aggressive and fiercely territorial. One pair that is typically documented are bears and wolves (very apt analog for Rex and Raptor). When environmental pressures are relaxed, they will not attack each other unless needed. They will even share a meal (insert picture of wolves and bears eating a beached whale here). A mutual enemy, when retreat is not an option, would be reason enough to team-up, in a anthropomorphic sense.
There are also plenty of instances of normally aggressive animals raising the young of others, or becoming friends in both domesticated and wild situations.
As for the movie, it can be boiled down to "You're no threat and I'm not hungry" on the T-Rex side, and "Your too big for me, your not attacking, and I'm not hungry" for the Raptor. Mutual disinterest as opposed to "respect" or any typically human emotion. The main consideration being threat, almost wholly dependent on size. A lone tiny Raptor is to a Rex like a Chihuahua to a Human.
Comment: Plus, after the battle where they had to team up to barely defeat the Indominus, there is the cost/benefit calculus that goes on when deciding whether to confront or not.  Sort of a "I'm not up for another battle, if I don't need to right now" factor, to my impression, as well.
Answer: Rexy fought the raptors in Jurrasic park but not the ones in Jurrasic world because they did not exhibit agressive or challenging behavior towards her. In fact they fought  alongside her against the unnatural hybrid.
Answer: In this video a paleontologist answers this exact question, in summary, it is not likely dinosaurs understand the concept of "help". There is no reason for the raptor help the T-Rex to begin with.
Answer: Tyrannosaur rex named Rexy was fighting against the Indominus because she was lured by Clair but her strength proven she was no match until nearly death saved raptor a common old enemy from her past that she killed named the big one and her minion. Though she understand be out of her captivity that raptors are enemy but since their were only three but she had killed two and the other one was frozen to death she became the queen of Isla nubler. With no real large predators but herself seems to think she the strongest until she met the I.rex but saved by Raptor as team to kill the evil threat made her realized that Raptor named blue had back off to show some respect to each other mostly moral reason. So rex quickly understood Blue as raptor isn't so much of threat compared her first time woth raptors 22yrs ago.
Answer: Its just a dramatic anthropomorphic moment, the kind you see two incompatible heroes have at the end of a movie just before parting ways after a brief period of collaboration to bring down the evil guy. Something like the final scene of

 Mad Max Fury Road.
Answer: There is no possible answer
even though the velociraptor and the tyrannosaurus rex were the two most feared dinosaurs the last velociraptor died 10 million years before the first tyrannosaurus was even born.


ANR Subsets  of  banach spaces

Question: I need   a  reference   for  conditions  on a  closed  subspace  of  a  Banach space  to have  the  homotopy  type  of  an ANR.
Comment: What sort of conditions are you looking form?
Answer: You could try Karol Borsuk's Theory of Retracts. There is extensive discussion of ANRs. Further related conditions can be found in shape theory (work in the 1970s by Edwards and Geoghegan) but that requires a knowledge of shape theoretic ideas. (That is why I asked what sort of conditions you were looking for as this is taking you away from the central area of Banach spaces).
Answer: (By subspace you mean topological subspace, right?).
You may try papers by Henryk Toruńczyk (and his students).

ANR Subsets  of  banach spaces


Proverb or expression for someone taking on too much

Question: What is an appropriate proverb or expression that means one has:

Taken on too many tasks
Set out to do something that one isn't qualified to do and hence probably will fail
Set out to do something that probably is impossible to begin with
Answer: For doing something that is too hard, or doing too much of it at one time, I'd say you could go with

Biting off more than he/she can chew

which usually implies "taking on too much/too may tasks", but I think it's fair to stretch it to "taking on a task that's too hard for you". This is, to me, the most obvious idiom for this, but it's fairly cliche.
You could also use

Getting in over his/her head  (as in, the water is too deep)

which implies swimming somewhere where your feet can't reach the bottom, and yet you're not a strong enough swimmer to handle it. You can also use

He's out of his depth/He's in too deep

which is the same metaphor.  Neither of these imply failure, since the speaker may have misjudged the swimmer/chewer. I can't think of a phrase that combines these with the notion that the task is impossible; usually impossible tasks are impossible for everyone and not just for one person (swimming in deep water may be impossible for him, in which case he's getting in over his head, but it's not impossible for me, in which case I just swim there).
Comment: +1 for "in over your head," though the others are perfectly acceptable as well
Answer: I really like Mr. Shiny's answer, and I almost just made this a comment there, but I suppose it deserves its own answer.
You can say that someone is engaged in a Herculean task. When used alone, the word herculean implies great strength, but an Herculean task connotes "requiring tremendous effort, strength, etc.", in reference to the seemingly impossible labors that were required of Hercules in Greek Mythology.
Because Hercules succeeded in his labors, this idiom wouldn't go quite as far as to say that the task is utterly impossible--only that you'd have to be on par with a demigod to accomplish it.
Update
Along the same lines, but with a stronger emphasis on failure, the American Heritage Cultural Dictionary has the following note on the definition for Sisyphus:

A difficult and futile endeavor may be called a "labor of Sisyphus" or a "Sisyphean task."

Either of these phrases requires at least a cursory knowledge of Greek Mythology, so they may not be appropriate for your audience, but saying that someone is engaged in a Sisyphean task seems to match your criteria well.
Answer: The only one not yet mentioned:
Too much on her plate.
Implies overcommitment and a lack of spare time.
Answer: You have listed  very specific criteria, and unfortunately, I doubt if there is actually one single idiom to describe all of that. One could possibly use a combination.
For "doing too much" :

Burn the candle at both ends.
  Bite off more than he can chew
  Carrying it too far.

For "illegal" :

You'll be caught red-handed
  Taking the law into his own hands.
  Fool's errand

For "impossible":

Flogging a dead horse.
  Nailing jelly to a wall
  Mission impossible

I would suggest, if you were to want a sentence expressing all three of your criteria, something like this:

You can't catch lightning in a bottle(impossible), besides, you'd probably be caught red-handed(illegal), and end up trying to burn the candle at both ends(do too much)
Comment: Just FYI, the singular of *criteria* is *criterion*.
Comment: +1 for biting off more than he can chew
Comment: @Robusto, should I use *criterion* in this case? I'm not sure, as he listed more than one condition
Comment: @Thursagen: If you can't work out number agreement for yourself, maybe you should ask it as a question on ELU.
Comment: @Robusto: I'd change it to "*some* very specific criteria", since you're talking about multiple "listed" instances.
Comment: Flogging a dead horse is not impossible - it's a very easy task. Just a futile one.
Answer: For "taking on too many tasks", I suggest spread oneself too thin or stretch oneself too thin. Its definition is:

To work on too many projects: overextend oneself.
Answer: A task that is beyond one's abilities can be likened to shovelling sand with a teaspoon, or, while we're at the beach, trying to empty the sea with a bucket.  These are the only metaphors based on common experience, rather than classical mythology, that come to mind right now.
Comment: If you would have read the accepted and most-upvoted answer first, maybe _biting off more than he/she can chew_ would have come to mind as well ;)
Answer:
Augean task     adjective Etymology: Latin Augeas, king of Elis, from
  Greek Augeias; from the legend that his stable, left neglected for 30
  years, was finally cleaned by Hercules Date: 1599 extremely formidable
  or difficult and occasionally distasteful
Answer: As I always told my smartest students,

The fact that you can do anything doesn't mean that you can do everything.
Answer: A common phrase for either taking on too many tasks at once or taking on something that's too difficult is biting off more than you can chew. I don't think there's an existing common phrase for taking on a task that's impossible. (You might just say "He's attempting the impossible" or "trying to do the impossible")
Answer: "Spread yourself too thin."
to try to do too many things at the same time, so that you cannot give enough time or attention to any of them:
Answer: For taking on too many tasks, you could describe having "too many irons in the fire"
Answer: William Shakespeare, Macbeth:
Life; is a tale told by an idiot, full of sound and fury, signifying nothing.
Given somekind of context, you could alter and say:
Life; is a tale and your an idiot, you fail to see the sound of fury, you signifying nothing.
Alternatively, from Confucius:
The hardest thing of all is to find a black cat in a dark room, especially if there is no cat.
I think these may all work for:

Set out to do something that probably is impossible to begin with


Why is keeping backyard hens inconsistent with veganism?

Question: If somebody keeps egg-laying hens in their backyard and makes sure they are loved and well cared-for, what's wrong with taking and eating their eggs from the perspective of veganism? If a person who identified as vegan was considering getting backyard chickens, what ethical considerations would you want them to be aware of?
Comment: What's the difference if it's a chicken or a cat? Do vegans not own pets? I mean, isn't that why everybody calls it "adoption" now, to make people feel better about buying a pet? If you don't eat your chickens, if you give your eggs to people who need them, if your hens have a great life and provide fertilizer to your garden, why give someone grief over it, like they're violating a law of some fundamentalist religion?
Answer: One of the philosophies vegans use is that it's wrong to use animals. This relates to other ethical philosophies that advocate treating people as ends in themselves and not as means to our own ends.
According to this philosophy, animals exist for their own purposes and confining them to benefit from them in any way is abusive, just as confining humans in order to benefit from them would be (if you know the movie, think of the machines harvesting human body heat in The Matrix).
Some vegans are willing to make some compromises around this area. Since healthy animals ovulate without intervention, and chickens do not make use of their unfertilised eggs, there is no obvious actual harm caused by using hen's eggs that are acquired incidentally from free hens. It may be the case that the kept hens have been rescued and would not be safe in the wild, and in such a scenario there might seem to be no ethical objection to eating the eggs.
Some vegans go on to consider the implications of selling eggs obtained that way. This is objected to as it is seen as using the animal as means to an end (obtaining money), though I am not sure how much more so selling is such "use" compared to eating yourself. A vegan who, for aesthetic reasons (disgust or distaste towards all animal-derived ingredients) does not want to eat the eggs, had better give them away freely. Then, not benefiting personally in any way from the use of the hen, they have not broken their own code... Still, giving, or selling eggs to people who would otherwise obtain them could be seen as creating or maintaining a market or demand for eggs, which can only be obtained according to these ethical standards in very small quantities. Since this "ethical" source cannot supply the entire market, it would be better for there not to be such a market.
These are some of the arguments usually made around this topic, one on which individual vegans take different positions.
Answer: @Zanna makes some good points and considers that:

"It may be the case that the kept hens have been rescued and would not
  be safe in the wild, and in such a scenario there might seem to be no
  ethical objection to eating the eggs."

However, in the vast majority of "backyard hen" situations, the hens are not "rescued," but rather are purchased.  The production of egg-laying hens has serious ethical implications, similar to buying poultry meat.  In particular, since roosters do not lay eggs and can create problems by fighting or make noise (and are sometimes specifically outlawed by local ordinance) the males are usually systematically killed at some (usually early) stage in the production of egg-laying hens.  Graphic videos of what happens to the male chicks abound.
Answer: According to the Physicians Committee for Responsible Medicine, eating eggs can cause heart disease, diabetes and cancer. Also, "Plant-Rich Diets" has been found by the Drawdown.org researchers as a top solution for climate change.
Aside for animal welfare concerns, there are are also ethical considerations related to health and climate change related to eating animal-based foods.
Comment: I think you meant to write that plant-rich diets are the top solution for climate change, not the top cause. (And it's #4, not the top solution.)
Comment: @Nic Thanks for the logic correction. #4 of 80 qualifies as "one of the top" solutions, but agreed: it is not the top solution, it is one of many to consider in parallel.


How can I remove a lemon from a toilet drain?

Question: My little boy flushed a whole lemon down the toilet. It is stuck. What can I use to remove the lemon?
Comment: My first thought would be a wire hanger, but if you plunge hard enough you might squeeze the lemon and allow it to pop into the 3" drain, it's amazing what pressure can do. Of course I'm considering the cheapest and quickest alternatives.
Comment: @hellomoto The intended purpose of a plunger is to *pull*, not to *push*.  Too much pressure, and you just lift the edges of the plunger and break the seal.
Comment: Have you tried using a plunger? How did that go?
Comment: @hellomoto I successfully extracted a "Shower Shroom" hair catcher with a wire hanger awhile back. I almost suggested that here, but I feel like the seal created by the lemon might be too much to squeeze it by and end up forcing it down further.
Comment: Caustic soda / /sodium hydroxide or drain cleaner based on this will destroy the lemon in a day or so.
Answer: There are attachments for coily drain snakes that have a cork screw type end on them. One example is like this:

Picture Source
Use of such attachment could screw itself into the lemon and allow pulling it out the way it went in.
Comment: I have jimmied blades to these auger tools and you basically just stab at the object over and over until it breaks up and goes down.   I have done this in toilets, sinks (needs a small blade to get past trap) and main stacks.
Answer: If you have access to a hardware store or can find one that ships it, you'll want a Toilet Auger
Answer: I'm assuming you're sure that the toilet is blocked by the lemon. Of course it depends on how tightly the lemon is wedged in the toilet. Toilets have a goose neck built into them that serves as a trap to provide a water seal. The lemon is almost certainly in that goose neck.
I don't know of anything safe that will dissolve the lemon that wouldn't be harmful to the toilet, the sewer/septic system and possibly to you. The only good solution I can offer is mechanical.
That involves removing the toilet giving you access to the goose neck from both ends and removing the lemon. It isn't a difficult job but does take some work and know-how. You will need to replace the seal that seals the toilet to the waste line.
The problem with other potential solutions such as pushing it through the goose neck can cause you more serious problems than you have now.
You might want to call a plumber to do this. If you want to do it on your own either I or someone else at this site can help you.
You might want to try Michael Karas' suggestion first. However, be sure to use a toilet-rated auger with the attachment. They have a protective sleeve to keep the auger from damaging the porcelain. Again, good luck.
Answer: If you have a shop vac try sucking it back out, removing the 'water' first or just sucking it up too and dealing with the shop vac clean up later. The better the seal of the hose end to the hole in the toilet the better of course. You might try a wet towel as a seal that will conform to fit. This actually might work better if the lemon has a tighter fit as it will create a better seal and therefore more vacuum pressure that can build up so that when/if it releases, it will have some momentum and hopefully come all the way out or at least close enough to reach in and grab it by hand.
Comment: Your comment got me thinking about the numbers, air pressure, one atmosphere is about 14.7 psi and I believe that the 'hole' or 'pipe' (I don't know what this is called) within the toilet is the same size as the outlet which I believe is 3" diameter. The area is then 7.07 sq in which equates, at a perfect vacuum, to 104 lbs of force, not too shabby
Comment: I know using a shop vac works. Never underestimate the power of a vacuum (negative air space) I have used a shop vac to  pull all sorts of things from dry and water filled pipes from 1/2" to 4" diameters.
Comment: You might try taking a toilet plunger head, cutting a hole in it slightly (1/8"?) smaller than the diameter of the wet-dry vac's wand, sliding it up the wand, and then back down the wand once it's in the toilet to form a tight seal when sucking water out of the toilet. Some grease on the wand (automotive grease, or just good old Crisco) would A) help the plunger head slide along the wand, and B) help ensure a good seal.
Answer: Pickling
A brine solution would suck water out of the lemon by osmosis. This could shrink the diameter enough to make it pass through.
The difficulties with this method are:

May take days to work.
Only one side would be exposed to the brine.
The lemon may have a wax coating to extend shelf life that would slow the process.
Complete mixing of the salt within the drain would need to be ensured.
Answer: By far the safest, fastest, easiest and cheapest method to unblock is to put a single large garbage bag over one hand and see if you can reach the lemon to dislodge it. If it's further down and not directly accessible, you can use your hand to create a plunging action which provides way more push pressure than any hardware-store plunger - you can increase the effectiveness of the plunge by adding toilet paper and filling up the bowl with water so that you have some hydraulic pressure also behind the push. Increase your chances again by adding some dishwasher liquid to make everything slide a bit better.
Dispose of the garbage bag after you've finished with it. For what it's worth this method also works a treat with other common blockages.
Specific to your question of dissolving the lemon - over time the lemon should change shape from dehydration or at least decay enough to dislodge so this should become more effective at later intervals. Just be sure to put an 'out of order' sign on the toilet until it's fixed. Not recommended to use anything caustic as even harsh acids wont actually eat into the lemon itself enough to make a difference and can be dangerous.
Answer: Use your hands and a cork-screw. The problem is you can't get a grip on the lemon and it's slippery.  Use the cork-screw to get a grip and just pull it out.
Answer: For actually dissolving the lemon (or at least enough of it to unclog the drain), ordinary NaOH (lye / caustic soda) based drain opener should work, at least as well as any other reasonably common substance would.
However, since the lemon is whole and presumably intact, it might take a considerable amount of time (as in perhaps days) for the NaOH to work its way through the lemon's skin and pith, which act as natural protective layers.  If you can manage to somehow poke a few holes in the lemon's skin, e.g. by sticking a piece of wire down the drain, that should help the process along quite a bit by exposing the soft and acidic flesh of the lemon directly to the NaOH.
(For maximum effectiveness, especially if using solid NaOH powder, pour some hot water in after it to help the NaOH dissolve and react faster.  Pre-mixing the NaOH with hot water is also possible, but if you do, make sure to wear proper eye protection while doing so!  The dissolution of NaOH in water generates additional heat that could easily make the water boil and splash hot caustic droplets around.  If you do get any on your skin or clothes, rinse it off immediately with lots of cold water!)
Note that I haven't actually tested this myself.  I do happen to have NaOH and some whole lemons around, so I'm kind of tempted to sacrifice one for science and see how long it takes for the NaOH to start acting on it.  I'm not sure it's worth ruining a perfectly good lemon, though.
In any case, physically removing the lemon e.g. using a toilet auger, as suggested in other answers here, is probably much easier and quicker than trying to chemically dissolve it — possibly even if you factor in the time needed to go to a hardware store to buy a toilet auger in the first place.  I would only suggest trying chemical methods if the lemon is stuck so deep that you really cannot physically extract it by any practical means.
Comment: In case you do try out NaOH, I can't overemphasize that you must be super cautious. Do NOT try mixing any water to it if you haven't handled NaOH before. Just pour the powder directly into toilet (with some care of course) ... and leave it for some time.
Comment: I thought of the same. Caustic soda can usually be bought in powder form (or small pebble sized chunks). These are usually used for cleaning drain pipes. My guess is that 200 grams of solid caustic soda in the toilet would make short work of the lemon in less than 15 minutes. At least it would be decomposed enough to be flushed.
Answer: In this case I would remove the toilet.  It may take a little work to get the water out enough to do it but is a far better method than trying to plunge the lemon through.  You may require a new wax ring before putting the toilet back on depending on it's condition.  Since you are this far, you may also want to replace the bolts that hold the toilet down, again, depending on their condition.  This is usually only a few dollars at the local hardware store.

Shut water off to toilet.
Empty water from bowl and tank.  Use a towel to soak up any excess you're scared might spill.
Disconnect the water supply.
Undo the two bolts at the base of the toilet
Remove toilet.
Find lemon.
Remove lemon.
Re-Install Toilet.

The problem with pushing the lemon through with the plunger would be it getting into your sewer pipes.  While a lot of pipes are 3-4" from the toilet it is no guarantee that this is true.  Also, different conditions of different pipes (cast iron pipes for example if your house is old enough) could cause restrictions and give you bigger headaches by plugging the main sewer lines in  your house; which usually in turn requires a plumber or at the very least, results in a bigger mess.
The worse thing I've ever had to remove from a toilet was a plastic drink cup (more than once) at our community hall.  It was enough to plug it, but soft enough you can punch a hole in it with a retriever snake which lets the water go through but renders you unable to retrieve it.  Removing the toilet was our only option.
Comment: I don't know about a lemon but I can tell you a kitchen sponge behaves similarly to the plastic cup described here.  Augers, reaching in by hand, nothing works.  Turning the toilet upside down and just taking it out took half an hour, including recaulking.  I regretted not doing it sooner after fighting with augers, snakes and plungers for weeks.  Always keep a donut in the garage.
Comment: "*7 Remove Lemon*"   That is the question. Perhaps you can **explain how to do that**. "*You may require a new wax ring*" Wax rings are not reusable, get a new one.
Answer: I flushed a lime down the toilet for fun today. I have a toilet auger so I thought it wouldnt be a big deal. It was a big deal. In the end though, the toilet auger did work. It took a lot of brute force and a ton of spinning the augur with pressure applied. I thought I might break something. The toilet was COMPLETELY clogged nothing was getting past this lime.
In the end I was able to pull out the augur which temporarily got stuck, and low and behold it had indeed corkscrewed its way through the lime and impaled it and the lime finally came out with it.
Thus, the augur might not seem to work, or might just want to push the citrus deeper, but enough twirling with pressure applied and elbow greese and you can indeed get it out with an augur.
Comment: In the future, try something else for fun,,,
Comment: Hey @JACK, differn't strokes for differn't folks! It was for _SCIENCE_! (and, if you've got a bathroom to spare until you can get a professional in, if you end up over your head, as it were, why the heck not?)
Comment: @FreeMan  I'll stick to  dropped two spheres of different masses from the Leaning Tower of Pisa ... :-)
Answer: Use a floor mop, the bigger the better
Push hard down so that you get downward water pressure.
Eventually it unclogs anything and everything!
Best trick ever!
Comment: Your answer is;  An object, that is larger then a pipe with a  curve in it, should be pushed further into the  **curved** pipe with a **straight** stick. **NOT** "*Best trick ever!*" Unless it works and the straight stick pushes the too large object through a curved pipe, then it is a miracle.
Comment: Before making your comment, did you try it? :)
Answer: I had a similar problem and my solution was to repeatedly pour in boiling water after removing the remain water from the bowl, about 5 liter in total, in an attempt to soften the lemon by heating.
After waiting half hour, the lemon easily squeezed thru the narrow trap, using an ordinary plunger.


Furnace blowing cold air

Question: Furnace wont produce heat. Thermostat is brand new. It Will work fine for a minute then heat come on go right back off. Can't find where filter goes house is old and vents are dirty I thought it's the filter but filter is new. Tired of feeling cold air instead of heat.
Comment: I'm confused, you say you don't know where the filters go but know you have a new filter, is the filter even installed? Are there any error indicators on the furnace? What model is the furnace and what type of fuel does it use (gas, oil, heat pump)? For gas/oil, does the draft inducer continue to run? For heat pumps, what does the outside unit do and is it clear of debris? From the description of the issue, it sounds like a flame sensor or high limit switch is shutting off the furnace.
Comment: See https://diy.stackexchange.com/questions/3653/why-is-my-furnace-blowing-cold-air
Answer: You should call an experienced HVAC contractor.
It sounds like one of the safeties on your furnace has failed and it is not initiating or detecting the flame properly (I am guessing you have gas, propane, or oil). So it begins to work, cannot initiate or detect the flame so it fails and it may just leave the fan running when it fails.
A service call will be worth it when you are warm again.
Good luck!
Answer: Be sure your filter is clean, low air volume will shut it off.
If you have unit that pulls combustible air from outside, check that orifice for blockage.
Check the vent for blockage.  I had a high-efficiency unit with a dip in the PVC pipe where condensate pooled and kept choking the unit.
If you can find a copy of your furnace's manual, check the front of the furnace on startup.  Most newer models have a display (LEDs generall) that gives some diagnostics and errors.  This lights have meanings, though sometimes general in specificity.  This may help you find the problem.
Also, if possible watch the burner.  All burners should light up and burn blue on a natural gas system.  Do not remove the cover if it does not have window.
Finally as ArchonOSX suggested, call a technician.
**Also get yourself a CO detector if you don't have one!

Furnace blowing cold air


How to get all the rice out of the pan?

Question: Often when cooking rice a lot of it ends up sticking to the bottom of the pan and gets wasted. I'm using a frying pan with a non-stick surface. Is there a way to get all the rice out of the pan easily?
Comment: What kind of pan are you using?
Comment: frying pan with a non-stick surface
Answer: I find that a silicone spatula is frequently better at getting the pan clean than a stiff spatula like a wooden one. If your rice is slightly burnt into the bottom, you might have to use both - scratch it off with the wooden spatula, then collect with the silicone one.
Answer: Other things you can try:

add a tablespoon more water at the start
reduce the cook-time by 2 minutes
let the rice sit for a minute or two with the lid on, sort of "steaming in its own juices"

The idea is that if the rice is just a bit damp, it won't stick.
Comment: I do the "let sit for a few minutes with a lid on" trick, it works for me every single time.
Comment: The last point is the key one.  Turn the heat off (or very low) well before the rice is fully cooked; with a lid on to keep the heat in, it will continue cooking just fine, but without further heat from the burner, there's no sticking on the bottom.  For cooking white rice in a heavy pan or a heavy hotplate, I usually turn the heat off straight as soon as the rice first comes to the boil.  In a light pan on gas or an induction hob, I'd turn the heat to very low at that point, and then completely off a few minutes later when the rice is mostly cooked.
Comment: Sometimes when the rice first gets soaked, it can adhere to the bottom of the pan.  If you leave them there, they won't come off without scraping even if you don't overcook it.  Once the water comes to a boil, I take a fork and stir the rice briskly to make sure it's free then turn the heat down and cover.
Answer: Try putting a spoon of fat (oil, butter, etc) in the beginning... it will melt and coat the rice/bottom of the pan. I used to always have some rice stuck to the bottom of my pan when I moved into my new home with gas stoves instead of electric. This trick works very well, and now my rice all comes out of the pan clean and easily.
Answer: When making sticky-rice I use a rice cooker with a non-stick surface on the inner pot. This works tremendously effectively. If you are using a frying pan with a non-stick surface then my immediate reaction would be that the contact point heat is too high. My second reaction would be to make sure you were rinsing your rice before cooking it (this helps with the extreme stickiness issue)
Comment: was going to say the same, never faced any problems with burning or sticking since I started using a rice cooker. the rice clumps together and comes out in almost one piece
Answer: Cook it in the microwave. It never sticks because the heat is applied evenly throughout.
Place one cup of rice with one cup of boiling water in a glass bowl with a tablespoon of oil.
Heat on full power for 6 minutes.
Stir the rice, add another cup of boiling water and heat for another 6 minutes. Then fluff it up once finished.
Once you cook it this way you will never go back.
Answer: I guess it depends on what you expect from your rice, but my recipe is this:

Heat up a pot with some (not too much) oil until the oil is quite hot.
Put some volume of rice into it, and vigorously scrape/mix it with whatever large implement you have around (big spatula).
Smell it a lot. At some point the rice will start to roast (ever so slightly), it may smell like nuts or something like that.
As soon as that smell changes, put in two volumes of cold water.
Let it get to boiling and immediately lower the temperature until it stays at an almost-boil. Stir occasionally (like every few minutes). Let it cook until the water is about gone.

For whatever reason, the rice never sticks, at least not more than can easily be swooshed off with a spatula (without any force, without getting any black burned residue).
I usually do that in stainless steel pots (very smooth surfaces). Occasionally I do it in a big wok with a noticeably rough surface, and there it works the same. So it should also work in a pan. I have not tried it in my cast iron pan.
Answer: I'm going to go contra to pretty much all the advice so far, but this is how I've been cooking rice for 25 years...
Clear-lidded pans make this far less guesswork.
Don't use a frying pan, use a heavy-bottomed saucepan with a tight-fitting lid, 3 times the volume of your finished rice.
Don't rinse the rice, you don't need to.
Use your coolest, most even burner - this is not necessarily the smallest. Sometimes the tiny ones generate bad hot-spots that a medium one wouldn't.
Boil the kettle.
Pre-heat the pan on high.
Add rice to your pre-heated pan.  Salt as required.
Immediately add 1.75 x the volume of water, not double.
That should immediately hit a rapid boil because of the pre-heating.
Stir once, just enough to ensure the grains are separated.
Drop the heat to minimum [on gas this is near instantaneous, you might need to wait a second on electric]
Put the lid on.
The contents should foam almost to the top but not go over - lift & replace the lid if it looks like it will go over, otherwise leave alone.
Simmer at this minimum temperature for 12-15 mins [depends how low you can get the heat]
Don't lift the lid to "see if it's done". Learn when it's done by repetition.
'When it's done' btw, is when all the water is gone; you might be able to hear a slight crackle as the last bit dries.
After the required time, switch off the heat, leave the lid on.
Allow to rest for another 15-20 minutes.
Fluff briefly with your spatula; no great effort should be required at this stage.
Serve.
The rice will be separate & fluffy, none will be stuck to the bottom.
This works for pretty much any rice type - long grain, basmati, or short-grain, glutinous [short grain, of course, will not separate in the same way].
Comment: "Don't rinse the rice, you don't need to.", you buy processed rice in bag of 500gr to 1kg right?
Comment: If by processed you mean 'ordinary' rice from a supermarket, yes; in 1 or 2kg bags normally. I usually have 4 or 5 different varieties at any time & will apply this same method to all of them. I never use that peculiar par-boiled 'easy-cook' stuff, if that's what you mean.
Answer: I agree with the suggestion of adding a very small amount of oil.  I pay attention to the taste and freshness of the oil I use, however small the amount, it influences the taste of the result.
Answer: Sticking rice usually happens because of a very high cooking temperature.
Your pot should be slightly boiling with the cap closed.
Answer: Let it cool and it won't stick, then you can scrape it out with a spatula rather easily.
Answer: Do what sushi chefs do when cooking rice, which is to use something like cheese cloth inside the cooking pot.  I bought one specifically made for rice, it's big enough to fit inside the pot folded over the rice and the water. AS the rice cooks and the water boils away, the net catches all the rice.  When the rice is cooked you grab the ends of the netting and pull the whole thing out of the pot.  voila, all the rice in the net.

How to get all the rice out of the pan?


"At the time" versus "at that time"

Question: If I want to say that during the accident there were no passengers, how do I phrase it?

There were no passengers at the time.
  There were no passengers at that time.
Answer: They are both correct, but "at that time" has that stilted, official-ese sound that some government employees like to affect when they are talking to the press. "At the time" is what normal people say.
Exception: if you are distinguishing between two times, especially between some former time and now, use "that".  E.g. (emphasis added) "The National Association for the Advancement of Colored People was established in 1909; at that time, 'colored people' was considered the polite phrase for 'black'."
Answer: at "that" time is usually used for sudden events. For example: at "that" precise moment police have arrived), where as at "the" time is used for events that happened long ago. For example: at "the" time of his birth...
Answer: at that time is used about a time in the historic past:
In Celtic Ireland women were allowed to own property, which was unusual at that time.
at the time is used about a particular occasion:
I didn't have any money on me at the time.

"At the time" versus "at that time"


How do default-free zone routers route IP packets if there is no matching route?

Question: From Wikipedia, about Default-free zone, it says:

In the context of Internet routing, the default-free zone (DFZ) refers to the collection of all Internet autonomous systems (AS) that do not require a default route to route a packet to any destination. Conceptually, DFZ routers have a "complete" BGP table, sometimes referred to as the Internet routing table, global routing table or global BGP table, but, realistically, the widespread use of route filtering and the rapid rate of change in Internet routing ensure that no router anywhere has an absolutely complete view of all routes, and any such routing table would, in any case, look different from the perspective of different routers, even if a stable view could be achieved.

I'm just wondering, if the DFZ receives a packet but has no matching route for this packet, what will do if it doesn't have a default route?
Answer: It returns a network unknown message (code 6) to the src address.
http://en.wikipedia.org/wiki/Internet_Control_Message_Protocol#Destination_unreachable


Good book for understanding the basics of SharePoint 2007

Question: One of my friends just got a MOSS 2007 project. But he doesn't know anything about it. So he asked me to recommend a book which will be very good for understanding the basics of SharePoint in a minimum time as he has a very little time to get all the basic concepts. So please I request to all, recommend a good book for this purpose.
Answer: If your friend doesn't know anything at all about SharePoint and is jumping into this, you may want to check out the SharePoint Shepherd's Guide for End Users by Robert Bogue - http://www.amazon.com/SharePoint-Shepherds-Guide-End-Users/dp/0615194494/ref=sr_1_1?ie=UTF8&s=books&qid=1276899050&sr=8-1
It will take them through the basics. I also love Dux's book that is mentioned above, it is excellent for Project Management specific use.
Comment: There are many good SharePoint books, but I cannot say enough good things about Robert Bogue's Guide for End Users.
Answer: You didn't really mention what your friend will be doing.  If it has anything to do with implementing, customizing, or developing solutions for the platform then I would highly recommend Professional SharePoint 2007 Development which provides a great overview of the architecture and how all of the pieces fit together.
Answer: I recommend Sharepoint for Project Management by Dux Raymond Sy:
http://oreilly.com/catalog/9780596520151
Or Seamless Teamwork by Michael Sampson:
http://sharepoint.microsoft.com/blogs/mikeg/Lists/Posts/Post.aspx?ID=1489
Answer: I recommend reading Microsoft's Inside Microsoft Windows SharePoint Services 3.0
this book is the best book for sharepoint beginners


Problems connecting to a friend's server in Team Fortress 2

Question: I can connect to other people's servers in Team Fortress 2 fine. I only have problems when I try to connect with a friend's dedicated server over the internet. Usually a message comes up and says that it "quit after 4 tries" or "server not responding". I know the server is responding, though, because the person running it and anyone on the same LAN connection can run it fine. I have tried using several other computers, maps, and ways to connect to the server, but nothing seems to work. What is the problem and how can I fix it?
Answer: If it's only people on the same LAN that can connect, then the problem is almost definitely to do with the server's firewall or, more likely, the router that your friend is using.
In the first case, it may be that the firewall is configured to accept connections from computers on the same subnet (i.e. on the LAN), but block connections coming from computers outside the subnet.  Set the firewall permissions on the server, and you're set.
In the second case, it's likely that the ports used by the server aren't being forwarded by the router.  The router doesn't know what to do with incoming connections that weren't initiated by one of the computers on the LAN, and the TF2 server might not be smart enough to tell the router that it's listening on port 270xx.  Forward the required ports using the router (web) configuration tool, and you should be good to go.
Here is some more information about setting up a server, and the needed ports.
EDIT: @Matthew Read posted a nice answer on a similar question listing the ports in use by Valve games.
Answer: One thing to check will be which IP you are using -
If you are using the same IP address as other folk on their LAN, it will most likely be a local address (192.168.x.x, or similar). This will not work over the internet, and you will need their external IP address.
They can get this from a website such as http://www.whatismyip.com/, or http://www.ipchicken.com.
They will then need to deal with forwarding ports to the server, as in MBraedley's answer.


What stuff can be safely removed for disk space sake?

Question: I am using Scientific Linux. So is there any stuff that can be safely removed from disk except /tmp?
Answer: One of the easiest and safest thing to do is to clear the package manager cache. You did not specify which operating system or distribution you use so I will give examples for the mainstream distributions:

debian/ubuntu:
apt-get clean

fedora/red hat:
yum clean

opensuse:
zypper clean

Most, if not all, other package managers in other distributions have a similar functionality.
Another thing you can relatively easy do is delete old kernel versions. Most distributions keep the old kernels installed when installing a new kernel.
Here is a guide how to remove old kernels for debian and fedora: http://www.cyberciti.biz/faq/proper-way-to-remove-old-linux-kernels/
Comment: Scientific Linux is based on red hat which in turn is based on fedora. I have updated my answer with information for fedora and red hat.
Comment: I am using Scientific Linux. Would you please note how to do it there?
Answer: If you want to reclaim disk space, the best way is to uninstall applications
you don't need. List the biggest applications that are installed and check if
you really need them. Since you didn't specify your operating system here's
how to do it on Debian based systems:
aptitude search '~i' --sort installsize -F '%I %p'

Another approach is to delete user data that's not required. To find big files
or directories, you can use a tool like
baobab.
Answer: All or much in /var/tmp can probably be removed.  Much in various /var/cache-directories - eg. previously downloaded apt-packages - can be removed.  In the users home-directories, thumbnails generated by various file-browsers (eg. .thumbnails) can be removed.  Also the caches of various web-browsers can be removed.
Answer: Beside getting rid of stuff you don't use, disk analyzing tools are also helpful because they help you find stuff you don't even think about. Maybe an application forgets to clean up its old logs, maybe old backups that you forgot about and don't need anymore.
The main difference is, instead of looking for stuff that you can delete, these tools show you the stuff that takes the most space, and then you decide whether that space is legitimate or wasted.
If you are on desktop I recommend baobab or KDirStat. For servers there is philesight.


Indian Citizen Getting Paid for Working as Writer for US News Organization

Question: I'm an Indian citizen. I'm doing a consulting role for a news organization in U.S. and getting paid on an hourly basis. The income would not exceed $1600 per month. The organization has asked me to file a W8-BEN form. Will my income be taxed? There is no slab for minimum income without tax? India and U.S. have a tax treaty. I don't know under which Article do I fall and the amount of tax that is deductible. Can you please help?
Comment: where are you located?
Answer: The W8-BEN form is used to declare your non-US tax status. This is used only for foriegners.
By declaring this form, that will not be with-held (Tax witholding is basically TDS in Indian terms).
In simple language, they will not deduct tax. They will pay you amount without deducting tax. It is upto you to see if you are liable to pay taxes in US or not and pay accordingly.
If you were a US tax payer, then normally they might deduct tax and then pay.
Read : http://en.wikipedia.org/wiki/IRS_tax_forms


How to define methodology for two different approaches?

Question: I am working on my Master Thesis and I am exploring two different approaches to the same problem. I am having trouble deciding on how to structure the Methodology section to divide these two approaches, since they share some components.
Answer: The best way to go about this is to be very clear about what you're doing. Label one as Methodology A and the other as Methodology B. Write them up separately and if then if you feel it necessary, write how they are similar.
When moving forward in your thesis be sure then to refer to each methodology explicitly in the context of what results were achieved et cetera.
As long as the reader is fully aware of what you're doing throughout, it shouldn't be a problem.
Answer: I decided that I'll divide methodology in 2 sections. One that is further subdivided into the two different approaches (which form the first steps in my pipeline) and the second section is what they share (the last steps). It looks something like this:
<code>Step 1
  Method A
  Method B
Step 2
</code>