I've just bought the above adapter after my old Belkin one gave up. I've seen a few solutions to peoples problems on here but haven't had any success myself yet. Which means this is coming from my phone. Not good.  The adapter doesn't seem to be working at all, the only time I can see it is lsusb- id 0bda:8179 realtek semiconductor corp. Is this what the adapter is meant to look like?  Running 10.04, kernel 2.6.32-45. I've tried installing the rtl8721 drivers, which comes up with 2 errors when I try to install it. Something to do with linux header package, but I'm pretty sure I've got them for my kernel. Tried blacklisting a few drivers but nothing's working. Will upgrading to the latest release be the quickest solution?  Sorry I can't copy more info across, as I said, working off my phone for now!  Thanks for any help  Tim
I installed Ubuntu yesterday, so I'm trying to get used to it.  I'm really close to my router, but my wifi signal gets too low. Sometimes I'm in Facebook or Youtube and the signal is high, almost full, but it is usually in one or two bars, and sometimes none.  I can use Internet normally, I can watch videos and stuff, but the problem is when I try to update something or Ubuntu is downloading stuff, the downloads get stuck or get cancelled telling me that I should check my connection.  How can I fix this? I should be getting a really good signal, I'm really close to my router, my phone has full signal, and a notebook with Windows 7 has full signal here too.  Sorry my bad English and I hope you can help me.  $ lsusb Bus 009 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 004 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 008 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 007 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 003 Device 002: ID 0bda:8179 Realtek Semiconductor Corp.  Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 006 Device 002: ID 0458:003a KYE Systems Corp. (Mouse Systems) NetScroll+ Mini Traveler / Genius NetScroll 120 Bus 006 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Help, i tried installing kaltools and my Ubuntu is messed up! I tried installing Kali Linux tools.  I started installing some tools and there were several things I had to "agree" to and one message said add users... something in terminal, and when I came back I saw terminal reporting removing a bunch of core programs that I needed. I canceled the process but I don't know if I should reinstall Ubuntu or not.  How can I repair my system? I have some pairs of datasets (n=200 or thereabouts), of samples which are non-negative and not normally distributed. I think these pairs of variables are related, probably linearly.   Calculating Spearman's rank correlation on these datasets gives some strange results. The correlation coefficients show that the pairs of variables are weakly, positively correlated (e.g. rho of around 0.4), but the p-values are very low (e.g. 4.1e-10).  My vague understanding of this is that the variables are weakly, positively correlated but the probability of unrelated variables producing the same correlation is very low. Does this mean we can be reasonably certain that a positive correlation exists or have I misunderstood? How to apply layer style to one object and apply it to multiple layers I will be attending a summer school which will last 10 days.  I want to know: for applying for a Schengen visa, is the purpose of my trip considered as touristic or study? Built-in unit strings recognized by Quantity? How to escape quotes in shell? I'm having trouble with escaping characters in bash. I'd like to escape single and double quotes while running a command under a different user. For the purposes of this question let's say I want to echo the following on the screen:  'single quote phrase' "double quote phrase"   How can I escape all the special chars, if I also need to switch to a different user:  sudo su USER -c "echo \"'single quote phrase' \"double quote phrase\"\""   Of course, this doesn't produce the right result. Asymptotic behavior of a trigonometric series Consider the following series $$S_N = \sum_{k=1}^N \frac{\sin[k\pi/(N+1)]}{k}.$$ What is the asymptotic behavior of this series for $N \to \infty$?  If we replace the sine function with the factor $1$, we get the standard harmonic series which diverges $\sim \ln N$. However, if we replace the sine function with $(-1)^k$, we get a convergent series with the result $\ln 2$. Therefore, I think that $S_N$, defined above, should diverge, but more slowly than the logarithm. Am I correct? Transit Visa for Thailand Terms for collections of animals As I watched the murder of crows sitting on the line above my house this evening, I got wondering where all of the collective nouns for animals (pod of whales, gaggle of geese, pride of lions) came from and why we need so many.    If sheep can be a flock, why can't whales, geese, lions, and crows? Difference between Analytic and Holomorphic function A function $f : \mathbb{C} \rightarrow \mathbb{C}$ is said to be holomorphic in an open set $A \subset \mathbb{C}$ if it is differentiable at each point of the set $A$.  The function $f : \mathbb{C} \rightarrow \mathbb{C}$ is said to be analytic if it has power series representation.  We can prove that the two concepts are same for a single variable complex functions. So why these two different terms? Is there any difference between these two concepts in general, please give example.  Thank you for your help. Some websites and textbooks refer to $$\Delta x \Delta p \geq \frac{\hbar}{2}$$ as the correct formula for the uncertainty principle whereas other sources use the formula $$\Delta x \Delta p \geq \hbar.$$ Question: Which one is correct and why?  The latter is used in the textbook "Physics II for Dummies" (German edition) for several examples and the author also derives that formula so I assume that this is not a typing error.  This is the mentioned derivation:     $\sin \theta = \frac{\lambda}{\Delta y}$      assuming $\theta$ is small:      $\tan \theta = \frac{\lambda}{\Delta y}$      de Broglie equation:      $\lambda = \frac{h}{p_x}$      $\Rightarrow \tan \theta \approx \frac{h}{p_x \cdot \Delta y}$      but also:      $\tan \theta = \frac{\Delta p_y}{p_x}$      equalize $\tan \theta$:      $\frac{h}{p_x \cdot \Delta y} \approx \frac{\Delta p_y}{p_x}$      $\Rightarrow \frac{h}{\Delta y} \approx \Delta p_y \Rightarrow \Delta p_y \Delta y \approx h$      $\Rightarrow \Delta p_y \Delta y \geq \frac{h}{2 \pi}$      $\Rightarrow \Delta p \Delta x \geq \frac{h}{2 \pi}$   So: Which one is correct and why? I wanted a list of sub-domains of Stack Exchange that are not mentioned over here   Some of the sub-domains I found which were not mentioned are       Are there any other which are not mentioned?    Mentions by , ,             Other mentions below which are not mentioned in "All Sites" but are mentioned in the drop down menu on the top left of the Stack Exchange website         Any other website that's left out ? Array only adds duplicate values How many objects are being created? I have been playing around with Ubuntu installing new themes and and docks. Sometimes during the installation, whole screen just hangs. What is the best way in Ubuntu to Kill a process/application? Anything similar to Ctrl + Alt + Del of windows? Edit:  I foolishly changed my example right before posting this. The following is what I meant to ask.  On the wikipedia page below, it says "a non-zero non-unit element in an integral domain is said to be irreducible if it is not a product of two non-units."   Then, on the wikipedia page below, it says "an irreducible polynomial is, roughly speaking, a non-constant polynomial that cannot be factored into the product of two non-constant polynomials."   The page then gives an example of a polynomial that is irreducible "over the rationals" (I assume it is implied that "the integers" is referring to the ring of polynomials over the field of rationals, right?)  $p(x) = x^2 + 2 = (x+\sqrt{2})(x-\sqrt{2})$  On the Wofram page below, it says "the irreducible polynomials are examples of irreducible elements."   If irreducible polynomials are a subset of irreducible elements, how is $x+\sqrt{2}$ a unit?  What can it be multiplied by to equal the multiplicative identity?  I think I have it right this time (sorry. long day)  ====================================================================  The following is the original post (for those who already responded and those looking at the corresponding responses)  On the wikipedia page below, it says "a non-zero non-unit element in an integral domain is said to be irreducible if it is not a product of two non-units."   Then, on the wikipedia page below, it says "an irreducible polynomial is, roughly speaking, a non-constant polynomial that cannot be factored into the product of two non-constant polynomials."   The page then gives an example of a polynomial that is reducible "over the integers" (I assume it is implied that "the integers" is referring to some sort of ring, right? due to the claim below)  $p(x) = x^2 + 4x + 4 = (x+2)(x+2)$  On the Wofram page below, it says "the irreducible polynomials are examples of irreducible elements."   If irreducible polynomials are a subset of irreducible elements, how is $x+2$ a unit?  What can it be multiplied by to equal the multiplicative identity? Show $\inf_f\int_0^1|f'(x)-f(x)|dx=1/e$ for continuously differentiable functions with $f(0)=0$, $f(1)=1$. Let $C$ be the class of all real-valued continuously differentiable functions $f$ on the interval $[0,1]$ with $f(0)=0$ and $f(1)=1$. How to show that $$\inf_{f\in C}\int_0^1|f'(x)-f(x)|dx=\frac{1}{e}?$$  I have been able to show that $1/e$ is a lower bound. Indeed, $$\begin{align*} \int_0^1|f'(x)-f(x)|dx &amp;= \int_0^1|f'(x)e^{-x}-f(x)e^{-x}|e^xdx \\ &amp;\geq \int_0^1\left(f'(x)e^{-x}-f(x)e^{-x}\right) dx \\ &amp;= \int_0^1 \frac{d\left(f(x)e^{-x}\right)}{dx}dx  \\ &amp;= f(1)e^{-1}-f(0)e^{0}\\ &amp;=\frac{1}{e}. \end{align*}$$ But how to show this is the infimum? Is there a function $f\in C$ such that we get $\int_0^1|f'(x)-f(x)|dx=1/e$? As the title suggests, I have some kit which is 200m from our current infrastructure (outdoors).  What is the cheapest way to establish a reliable connection across a 200m stretch (Cat 5e ethernet only works up to about 100m from our tests)? Is transferring to another university an option for an unhappy PhD student? I've heard of people transferring between graduate schools because of their advisor moving to another school and taking their students with them.   Do students ever transfer for other reasons? If a student isn't happy at the school they choose, could transferring be an option? Presumably they would frame it as something positive such as "turns out I really want to work with Professor X" rather than "I hate my school", but does this ever happen? Is there a certain timeframe in which this is possible? (Assume it's a 5 year PhD program.)  If the answer varies by subject please mention the subject in your answer.  (Context: many friends have told me that if it turns out I'm not happy with my choice, I can always transfer. My impression is that this is actually difficult since many schools don't accept transfer students and in any case not being able to stick with a program looks bad -- but I don't have evidence either way so wanted to ask people who are in academia. Of course the ideal would be to pick a school one is happy with in the first place!) Flagging summary improvement: filters