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A few year ago I made a list about all my computers. I thought, it would be nice to make a new one:

Lenovo Thinkpad X1 Carbon – Main computer (work and personal)

  • CPU: Intel Core i7-3667U, 2 GHz
  • Graphic Card: Intel HD graphics 4000
  • Memory (RAM): 8 GB
  • Ports: 1x USB 3.0, 1x powered USB 2.0, mini-display port, microphone/earphone port, 4-in-1- card reader
  • Onboard storage: 180 GB SSD
  • Wireless: Bluetooth, W-LAN, GSM/UMTS/HSDPA/HSUPA
  • Display: 14″
  • Weight: 1.36 kg
  • OS: Win 7
  • Mainly used for: backup of Iphone & Itunes library (Itunes), work emails (MS Exchange), personal/work calender (MS Exchange), writing (MS Office, TeXworks), receiving SVN files, simulations (Matlab), online research (Firefox), other personal & work stuff

Lenovo Thinkpad X220 – Work laptop (for simulations)

  • CPU: Intel Core i7-2620M
  • Graphic Card: Intel HD graphics
  • Memory (RAM): 8 GB
  • Ports: 3 x USB 2.0 (one powered),  4-in-1- card reader, VGA, display port
  • Onboard storage: 320 GB HDD
  • Wireless/Communication: Ethernet LAN, W-LAN, Bluetooth, UMTS
  • Display: 12.5″
  • Weight: 1.67 kg
  • OS: Ubuntu
  • Mainly used for: receiving SVN files, online research (Firefox) and simulations for work

Streaming (online and DVB-T) / Data / E-Mail PC

  • CPU: Intel Pentium D, 3,2 GHz x 2 (I really need to upgrade the CPU and main board: The CPU fan is just too noisy)
  • Graphic Card: Nvidia GeForce GT630
  • Memory (RAM): 2 GB
  • Onboard storage: 240 GB
  • OS: Ubuntu
  • Mainly used for: DVB-T (Kaffeine), online streaming (Firefox), E-Mails (Thunderbird), data storage / backup

Banking PC

  • CPU: AMD Athlon 64 3500+, 2,21 GHz
  • Graphic Card: Radeon X1900XTX
  • Memory (RAM): 1 GB
  • Onboard storage: 240 GB (SATA)
  • OS: Ubuntu
  • Mainly used for: Online banking (Firefox)

Raspberry Pi – Model  B – Media Center

  • CPU: ARM1176JZF-S (700 MHz)
  • Graphic Card: Broadcom VideoCore IV GPU
  • Memory (SDRAM): 512 MB
  • Ports: 2 USB 2.0
  • Video Output: FBAS, HDMI
  • Audio Output: 3.5mm jack, HDMI
  • Onboard storage: SD / MMC / SDIO card slot
  • Communication: Ethernet LAN
  • OS: Openelec
  • Mainly used for: watching DVD films

And of course various HDDs for backup.

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I bought a new DVB-T stick (my old one was so old, that it is not even supported by Windows anymore… I think even under XP it was not possible to use). I bought a really cheap one: I don’t watch TV that often and normally the online streams are enough. But sometimes there are no online streams at all or they are not live or the connection gets lost. So a cheap one is really fine. I am really happy that the one I chose (CSL DVB-T Stick with a Realtek-Chip) is functioning also under Ubuntu (and, of course, also under Win 7), since my streaming PC (connected to the TV) runs with Ubuntu. 🙂 Installation was (surprisingly) simple: With my last stick, it even took some effort to make it run under Win, but under Linux? Not possible at all!

I just installed Kaffeine (compared to the Win Software on the Stick-DVD (TotalMedia), it is so much nicer to use) and followed the steps under https://help.ubuntu.com/community/DVB-T_%28USB%29. On the page you can also find an instruction, if you card is not (generally) supported. My Stick was not on the list, so I recommend you to first try the following steps:

Get the required packages:

$ sudo apt-get install git linux-headers-$(uname -r) build-essential patchutils libproc-processtable-perl

Fetch source code:

$ git clone git://linuxtv.org/media_build.git

Change to the directory created before:

$ cd media_build

Compile the code (takes some time):

$ ./build

Install the compiled code:

sudo make install

Restart your system. Start Kaffeine, select an appropriate Source and search for the channels.

 

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I wanted to structure the computers I have and use a bit better:

I have a Thinkpad X220 from work with Ubuntu for working stuff.
(Of course there is also my desktop pc at work…)

Then I have a Thinkpad X1 Carbon: This is the computer I usually use. I use it for personal stuff, work related stuff, it has Itunes, Exchange (from work) with my work-mails and (most important) my calender (work/personal) and some other programs I use.

I have a Desktop PC with Ubuntu for data storage and email storage (I have one mail account I access directly on my iphone, I can access the others ones from this PC).

I have a Raspberry Pi (Modell B) with Openelec as a media computer: It has a backup of my DVD collection. Openelec is quite nice: It offers a nice menu where you see the movies, some short description and so on and you can control it with the xbmc iphone app directly from the phone. The only thing missing is “standard” webbrowser:
I have satellit tv in my flat, but don’t want to have a receiver. I also do not watch much the normal tv program (the few things I watch are also available online directly from the television transmitters). At the moment I just watch the stuff on my Thinkpad, but I got the idea that I could simply take my data storage desktop PC, connect it to the TV and use it also for streaming from the television transmitter websites. On the Raspberr Pi streaming is difficult: You get problems with the usually necessary (for streaming) Flash Player and I also read that it is too slow for really using it for streaming. Also my Wii U did not have the necessary version of the Flash Player, so it was also not possible to use it for this kind of application.

Last but not least: My old media-computer: It was used for watching DVDs and other media before I got my Raspberry Pi. I havent’t really used it afterwards. But now I will install Ubuntu on this one an will use it purely for online banking. I havent’t used online banking up to now because of the security risks there… But I mean: The bank will nevertheless store your informations and transfers somewhere, so this point against online banking is out… The next thing: Trojaners could access your online banking account or someone could hack into it: If I use one pc purely for online banking, only type in the adress manually, don’t click any links, the risks are minimized. Of course: Use a strong password and change it often. 🙂

But for using desktop and old-media pc, I had to “repair” them (okay, if you call fixing the CMOS checksum error a repair 😉 ) and change some components: I exchanged the graphic cards (the desktop/streaming PC needs to be connected to the TV now and I wanted to use the HDMI port of the old media PC’s graphic card), bought a new PCI Wlan Card (put this in the desktop/streaming PC and the old one from there in the old media PC).

Really a fun evening. 🙂 Everything is functioning as it should and I did not get any problem (at least so far, the desktop/streaming PC is finished, but I have to install Ubuntu on the media PC which shouldn’t cause any problems).

/Update: Everything is finished and working as it should. Although… I should really update the mainboard and RAM of the desktop/streaming PC: Streaming is functioning, but a bit slow (or was it just because I tested it with ARD where a WM game is shown and too many people are watching?! I will test tomorrow again…)

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For incorporating new .sty style sheet files using TeXworks / MikTeX on windows do the following:

  • Create a folder (e.g. C:/Local Tex Files/tex/latex/misc) and put the new style sheet file (e.g. “myfile.sty) in there
  • Go to MikTeX settings and in the tab “Roots”. Click “Add” and select the folder you created before
  • To use the new style sheet in your document: Add “\usepackage{myfile}” to the document preamble

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I found a very nice book for a first contact with the topic Electricity. It should be really used in schools, since it teaches basics about electriticy, circuit components, creation of electricity, … by using manga form and a sweet story. I think the authors really succeed in writing the book in an understandable way and they find nice analogons (e.g. explaining voltage/current with water flow). There are also some pages in text-form to tell more details. I really enjoy reading the book, even if nothing really new or suprising is in it for me. There are also more books in the “The manga guide to” series, e. g. Calculus, Physics, Statistics, Databases, Relativity, Molecular Biology, Biochemistry and Universe. I should really buy the rest of those books too.

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It is really terrifying how ill-prepared some students are in exams. Okay, I really understand that you do not like every subject you must take during your course of studies, but I think that you should at least try to revise the important stuff. Most of the times this is all it takes to at least pass the exams, even if your grade is not good. But how can you go to an exam when you not even know the basic facts!? A very good example what you shouldn’t write is the following. And yes, this is something a student really wrote in an exam!! (Okay, the student did not paint a flower, but I wanted to anonymous this case. So yes, the picture you see with this entry is not the real painting this student painted.) The student wrote that he does not know how to solve the problem and that he will paint something instead. And so this student painted a flower…

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Do you have problems with the multiplication of  large numbers? Or do you have kids and want to show them an easy way to multiply two numbers? Then you should probably watch the following video.

I think this method is really useful. With it the only difficult thing left when doing multiplications is the drawing of straight lines. 😉

[via gizmodo.com]

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