This is the RAID0 structure:    there have 3 disks,  I have a question about this, when write data into disk, is it write disk A full, then write disk B?   or is write a little data into disk A, then write into disk B a little, then write to disk C a little?
This is a  about RAID levels.    What are:   the RAID levels typically used (including the RAID-Z family)?  deployments are they commonly found in? benefits and pitfalls of each?
How do I change NEI to cheat mode? When I heard that you could look up recipes and cheat items with Not Enough Items, I downloaded NEI. It worked, and then I got another mod and the all of a sudden NEI still worked, but it was locked in recipe mode only. I tried fixing it by putting it into cheat mode again, but it was still in recipe mode.  I knew the only reason this happened was probably because of a change in the mod. Then I was watching a YouTuber who had the same exact mod as me and NEI was working and not locked in recipe mode for him. I tried redownloading NEI and getting it again but I was still stuck in recipe mode.  How do I get NEI in cheat mode? Cycles in SHA-256 Let's say I start with a particular 256 bit value. Call this $v$. I then hash that value, and get another 256 bit value. Call this $\text{SHA256}(v)$. I take this value and get another 256 bit value. Call this $\text{SHA256}^2(v)$. More generally, let's call the result of hashing $v$ repeatedly $n$ times $\text{SHA256}^n(v)$.  Now my question is, how big will $n$ be, such that $\text{SHA256}^n(v) = v$?  It would seem to me, that if it's a giant sort of permutation, $n$ would have to be $2^{256}$, is that correct? Is that provable, or is there any information on this? (Just curiosity, really.)  Another question I had was, do all 256 bit strings have unique SHA256 values, and is there a way to show that? (Or, stated differently, can it be shown that there are no SHA-256 collisions in the language of all "256 bit strings"?) Is it possible to make an underfull tabulary spread out? How to strike through obliquely, e.g. to indicate cancellation? Constructing an explicit isomorphism between finite extensions of finite fields Suppose $K$ is a finite field, $K = \mathbb F_{p^s}$. If we take an irreducible polynomial $f$ of degree $d$ over $K$, then the splitting field $L$ of $f$ is $K(\alpha)$ where $f$ is the minimal polynomial of $\alpha$. But then $L = \mathbb F_{p^{sd}} $. Since $\mathbb F_{p^{sd}}$ is unique, we see that this is the splitting field of every irreducible polynomial of degree $d$ over $K$.   Take $K = \mathbb F_2$ and let $P(X) = X^3 + X + 1$, $Q(X) = X^3 + X^2 + 1$. Let $L$ be the splitting field of $P$ and $L&#39;$ be the splitting field of $Q$. The above tells us that $L$ and $L&#39;$ are isomorphic. I would like to construct an explicit isomorphism between $L$ and $L&#39;$.   I know that $L \cong \mathbb F_2[X] /(X^3 +X + 1)$ and $L&#39; \cong \mathbb F_2[X] / (X^3 + X^2 + 1)$. Intuitively, I want to find an isomorphism $\phi : \mathbb F_2[X] \to \mathbb F_2[X]$ such that $\phi((X^3 + X + 1)) = (X^3 + X^2 + 1)$. A little playing around gives me $\phi(X) = X+1$. It now feels like I'm falling at the last hurdle: how do I finish the construction of an isomorphism between $L$ and $L&#39;$? I don't think $\phi$ makes sense as a map from $L$ to $L&#39;$, yet it seems the map I want. Can "zero hours contracts" be considered as not grammatical? Possible Duplicate:          I sometimes work outside and are using a 3G usb connection with quite a limited data allowance.  I want some fast and easy way to temporary block all incoming and outgoing traffic in windows firewall except for chrome to be sure that Dropbox or something else is not using up my data.  I've tried to set Windows Firewall Properties to "Block" which gives "Outgoing/Incoming connections that do not match a rule are blocked".  Problem: There are many allow-rules like Dropbox that would "override" the block. And I don't want to disable all rules and then enable them, since there are some that I want disabled even when I get to the office...  Any suggestions?  Thanks! In convex optimization, the feasible region is convex if equality constraints $h(x)$ are linear or affine, and inequality constraints $g(x) \leq 0$ are convex. Does this mean that if $h(x)$ is nonlinear, then the optimization problem is non-convex? Is there any special case where $h(x)$ is nonlinear and the feasible region is still convex? Find $n$ such that $n/2$ is a square, $n/3$ is a cube, and $n/5$ a fifth power Uniform convergence on two separate intervals Test the sequence of functions for uniform convergence       $$f_n(x)=\frac{nx}{1+n^2x^2}$$      $a) \text{on} \ [0,1]$      $b) \text{on} \ [1,{\infty})$   a)  If we differentiate this with respect to x we get the following :  $$(\frac{nx}{1+n^2x^2})'=\frac{n(1-n^2x^2)}{(1+n^2x^2)^2}$$  This is equal to $0$ for $x=^{+}_{-}\frac{1}{n}$  From here we can either check these two values in the original function and take the larger one as the supremum or we can find the second derivative and check whether it's negative. In either case we find that for $x=\frac{1}{n}$ we get the value $f_n(x)=\frac{1}{2}$ and for $x=-\frac{1}{n}$ we get $f_n(x)=-\frac{1}{2}$. Note that $x=-\frac{1}{n}$ doesn't even belong in our interval. Now we can finish the problem.  $$\lim_{n\to \infty}{\frac{nx}{1+n^2x^2}}=0$$  So it is piecewise converging to $f(x)=0$  $$\lim_{n\to \infty}\sup{\left \lvert{f_n(x)-f(x)}\right \rvert}=\lim_{n\to \infty}{\frac{n\frac{1}{n}}{1+n^2 \frac{1}{n^2}}}=\frac{1}{2}$$  So $f_n(x)$ does not convergence uniformly on $[0,1]$ to $f(x)=0$  b)  Now we need to test the on the interval $[1,\infty)$.From the first derivative we notice that if $x\in [1,\infty)$ then the numerator seems to be negative for all $x&gt;1$. So $f_n(x)$ is monotonically decreasing. That means that the supremum will be at the first point of the interval or $x=1$. Taking the limit :  $$\lim_{n\to \infty}{\frac{n}{1+n^2}}=0$$  We can see that the function convergences uniformly on this interval.  Is there something wrong with either of these solutions?  I'm having doubts mostly about the second interval since $x=\frac{1}{n}$ is a supremum but only for $n=1$. However I believe that we need to have the supremum that's satisfied for all $n \in N$. Pointing even the tiniest mistake in my solutions would be very helpful. Thank you. "Thanks for having me" Recently, I finished my phone job interview with the phrase "Thanks for having me". It was a reply to the other person's "Thank you for your time". So, does "thanks for having me" sound alright in this context? What does DISPLAY=:0.0 actually mean? Omission of verbs This following sentence is puzzling me. Neither can I understand the meaning, nor can I reason the grammatical soundness of the sentence.     Some symbols acquire a multitude of meanings, some widely shared, others personal, some contradictory, conflicted, or ambivalent.   Please help understand the meaning and grammatical explanation. Word for seeing both sides of an argument At least two questions (, ) on this site indicate that in more than a few isolated cases at least, letters of recommendation are in fact written by the applicant and only signed off (or perhaps rephrased somewhat) by the recommender, who would actually be responsible for writing the letter.  Is there any evidence about the prevalence of this practice that goes beyond anecdotes? I realize that cross-country (cultural) difference may play a role. How can I make a surface look wet in cycles? I am trying to recreate a wet road with lights reflecting off of it. I started by making the object glossy but this did not give a very realistic look  I think I need to increase the specularity of the reflection to make it look more real but I can't find this option anywhere in cycles. Also what other techniques can I use to make a surface look wet in blender? I can link directly due to licening but  is what I am trying to recreate. What are the alternative Android app markets? How many competing Android markets (other than the Play Store itself) are there and are they any good?  Which ones do you use and why? Often, TeX outputs underfull hbox and vbox warnings when running and in the generated log file. What are these and how can I get rid of them? How does accepting an answer work? What does it mean to accept an answer? How do I accept an answer, and what are the rules? Can I accept my own self-answer? What are the reputation benefits? Which answer should I accept? Should I upvote the accepted answer? What should I do if none of the answers are suitable?      For more information, see "" in the . Another "can't use Alt. Series Conv. test" (How do I determine if it converges or diverges?)