I received call one of a company. They are implementing and installing Ubuntu Desktop OS in there client systems and they need:      Create one user as a temporary user and that user should have 3 options enabled in client system:          google chrome with one fixed URL(http:192.168.1.1)    printer access for printing    scanner access for upload docs.          All remaining functionality should be disabled.    For the above process, what resources do we have to use and how can we disable everything? The Company is asking to make a professional document for the above installation. Please help me with this issue.
I would like to customize ubuntu for a library, they only want to display a web browser with their site in full screen.  No address bar, no button user can only click the link on the page.  If library's staff enter admin user name and password they can change any settings in ubuntu.  Any suggestion or usefully link is much appreciated.
Force ssh to not print "Remote host identification has changed" warning Is there a way to avoid ssh printing warning messages like this?   @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ @    WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!     @ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@   Although the remote host identity has changed but I know it is fine and  just want to get rid of this warning. Java rounding to nearest 0.05 Outlook, POP and PST handling Essentially I have a client who is on hosted exchange and have decided to use POP3 to download the mail (I don't know why they don't use .OST's but anyway), they rebuilt the machine and backed up their .PST file. Now their Outlook was configured to keep mail downloaded on the server for 14days.  Essentially their current PST is fairly complex, many folders and sub folders and so on. So what is the best way to handle it really - create a new Outlook profile on the rebuilt machine and download the mail via POP into a new .PST then just recreate the folders in the new pst and drag and drop the mail via attaching the backed up .pst, recreating the folders etc?  But is their an easier way to do this, maybe pointing the new account to use the original PST, but then that would download all the mail again from the server to that .PST file.  Any ideas on the best way to handle POP3 account rebuilds from scratch when you have a backed up PST? Which is the preferred way to convert an Enum to a String in .NET 3.5?   Enum.GetName Enum.Format ToString   Why should I prefer one of these over the others? Does one perform better? My question is simple, why do we believe  to be absurd? Is the Ultra-violet catastrophe incorrect or is it only because we can not create or know of a perfect emitter? I am a bit confused as to why Quanta was necessary. Calculate battery life I would like to know how to calculate battery life when using an LED strip. The LED strip is powered by 8 AA batteries in series. LED Current Draw = 260 mA. LED power consumption: 3.1 W. LED Operating Voltage range: 9-14.8 VDC. Please see attached images for battery datasheet.  This is my calculation, but I'm not sure if it's correct:     Battery Life = (Battery Capacity)/(Load Current) = 2000 mAh /260 mA = 7.7 Hours   This is for one battery, and the lights are powered by 8 batteries, so is the total battery life = (7.7)x(8) = 61.6 hours ? In Ubuntu releases prior to Ubuntu 19.10 Eoan Ermine, when I run a command with sudo, that command receives my home directory in the $HOME environment variable. This is the behavior I have long expected and . If I want sudo to reset the $HOME environment variable, so that it refers to the target user's home directory instead of my own, I have to pass the -H option (or -i, though that does more).    ek@Kip:~$ lsb_release -d Description:    Ubuntu 18.04.3 LTS ek@Kip:~$ sudo printenv HOME  # Shows ek's home, not root's. /home/ek ek@Kip:~$ sudo -u as printenv HOME  # Shows ek's home, not as's. /home/ek ek@Kip:~$ sudo -H printenv HOME  # Shows root's home. /root ek@Kip:~$ sudo -Hu as printenv HOME  # Shows as's home. /home/as   When I first upgraded to Ubuntu 19.10, I was surprised to discover that sudo seems to reset $HOME no matter what! I continue to observe this now that 19.10 is released and I've installed updates--both on newly installed systems and one I upgraded to 19.10.  ek@Cord:~$ lsb_release -d Description:    Ubuntu 19.10 ek@Cord:~$ sudo printenv HOME  # Shows root's home, even without -H or -i. /root ek@Cord:~$ sudo -u as printenv HOME  # Shows as's home, even without -H or -i. /home/as ek@Cord:~$ sudo -H printenv HOME  # Also shows root's home. /root ek@Cord:~$ sudo -Hu as printenv HOME  # Also shows as's home. /home/as   I thought this might be due to .  But I checked, and always_set_home does not appear in any Defaults line in my 19.10 /etc/sudoers file.  What makes sudo treat $HOME differently starting in 19.10, and why was this change made? Does this make it safe to use plain sudo in cases where I would previously have used sudo -H? How do humans dominate the Federation in Star Trek? How can I prevent spam on sites which I control? This is a general, community wiki question to address all non-specific spam prevention questions.  If your question was closed as a duplicate of this question and you feel that the information provided here does not provide a sufficient answer, please open a discussion on .    For purposes of this question, spam will include:   Any automated post Manually-posted content which includes links to spammers' sites Manually-posted content which includes instructions to visit a spammer's site Suppose I have BaseClass with public methods A and B, and I create DerivedClass through inheritance.  e.g.  public DerivedClass : BaseClass {}   Now I want to develop a method C in DerivedClass that uses A and B.  Is there a way I can override methods A and B to be private in DerivedClass so that only method C is exposed to someone who wants to use my DerivedClass? Can 'AMD-only' RAM really be restricted to AMD chipsets, and if so, why? I was browsing for a RAM upgrade earlier for my system, and came across 'AMD-only' RAM (aka, RAM that only works on AMD chipsets).  This RAM can , and seems to be slightly cheaper than 'normal' RAM.  The RAM prompts a question: is this RAM really restricted to AMD chipsets?  When considering RAM for a system, there are certain considerations to make such as:   Speed (1066MHz, 1600MHz, etc); CAS (latency, lower is better); Generation (DDR2, DDR3, DDR4, etc)   However there is usually no such consideration as chipset compatibility. Sure, it's possible to guarantee that a given stick of memory will work if it's within the bounds of the chipsets listed in the information given by the seller/manufacturer.  For instance if a series of chipsets supported RAM between 1600MHz and 2400MHz, with 9-12 CAS, and on DDR3, it would be possible to list a product as being fully compatible with that series of chipsets if the said RAM was 2000MHz, 10 CAS, and DDR3.  I suspect that's partially the story here. However, is it possible at all for a given stick of memory to be 'AMD-only' or 'Intel-only', and if so, how? Determinant of block matrix with commuting blocks I know that given a $2N \times 2N$ block matrix with $N \times N$ blocks like   $$\mathbf{S} = \begin{pmatrix} A &amp; B\\  C &amp; D \end{pmatrix}$$  we can calculate $$\det(\mathbf{S})=\det(AD-BD^{-1}CD)$$ and so clearly if $D$ and $C$ commute this reduces to $\det(AD-BC)$, which is a very nice property.   My question is, for a general $nN\times nN$ matrix with $N\times N$ blocks where all of the blocks commute with each other, can we find the determinant in a similar way? That is, by first finding the determinant treating the blocks like scalars and then taking the determinant of the resulting $N\times N$ matrix.  Thanks in advance! Let $(\Omega, \mathcal F,P)$ be a probability spaces and $H$ be a Hilbert space. By a random operator $A$ from $H$ to $H$ we mean a linear continuous mapping from $H$ into the Frechet space $L_0^H (\Omega, \mathcal F,P)$ of all $H$-valued random variables. My question is: How Can we define $|A|$ and the adjoint $A^*$? What do the fields in ls -al output mean? Free, open-source substitutes for Mendeley? is (mainly) a proprietary social network to share basic citation data and research papers.   Are there any free and open source substitutes for this service?   A technical possibility: users could collect BibTeX data and a hash and share this information.  It would be very useful to have such a free service because every journal provides the citation data in a different format. That includes false field entries, broken files and hidden download buttons on the website. Probably a novice question, but how do I correctly diagnose from a photo for what reason that camera wasn't able to focus properly?  It can be any 1 of the following   Unsteady hand Lens issue Metering Re-Calibration required in camera or ...   Is there a set of unsaid protocols that needs to be followed by a photographer?  Goal is to get a sharp and crisp image prior to editing.  [PS: I own a Nikon D5200.] How to render world position pass Do I have to pay taxes in the US if my online store sells to US customers even though I don't live in the US? I  own a website and I sell digital content. I'm a nonresident alien with the US. Most of my customers are US based so I was wondering will I have to pay any taxes to the US?  I have read that      For nonresidents, taxable income is separated into two categories:         Income that is effectively connected with a U.S. trade or business, after the deductions that are allowed, is subject to U.S. income tax   at graduated rates - the same rates that apply to U.S. citizens and   residents - or lower rates if the provisions of a tax treaty apply.   Income that is subject to U.S. income tax, for being U.S. source income, but that is not effectively connected with a U.S. trade or   business, is subject to a flat 30% tax      Is this true and do I belong to any of these categories?  If I form an LLC or C corp am I liable for this withholding tax?  My customers are based in the US and I believe all income is considered FDAP income according to the IRS:     Fixed, Determinable, Annual, or Periodical (FDAP) income is all   income, except:         Gains derived from the sale of real or personal property (including market discount and option premiums, but not including original issue   discount)   Items of income excluded from gross income, without regard to the U.S. or foreign status of the owner of the income, such as tax-exempt   municipal bond interest and qualified scholarship income      The thing is the IRS also says:     Effectively Connected Income, after allowable deductions, is taxed at   graduated rates. These are the same rates that apply to U.S. citizens   and residents. FDAP income generally consists of passive investment   income; however, in theory, it could consist of almost any sort of   income. FDAP income is taxed at a flat 30 percent (or lower treaty   rate) and no deductions are allowed against such income. Effectively   Connected Income should be reported on page one of Form 1040NR. FDAP   income should be reported on page four of Form 1040NR.   In the last quote, it’s like they say it only applies to passive income but if they feel like it, they can apply this to all income?? Converting KML to shapefile without losing attributes using QGIS? Lubuntu 16.10: How to make login through greeter without typing password work