AWN

Last week, I watched an appealing desktop environment for Gnome to resemble the Mac OS desktop. I was very curious about it and I did a non-deep search and found this project Gnome theme named Mac-OSX. I did install it and it presented me a better desktop than my previous one. However, the dock panel present in real Mac OSX was not there. I googled for "mac like dock in linux" and found some interesting links:

• This link explains a little bit about the AWN project and describes how to customize this window manager
• AWN has a wiki site
• This link explains how to start the awn window manager

I will restart my gnome session.

Tip:

• As root, run the following command: "yum install awn-extras-applets"
  

Configuring and Installing HP Photosmart C4780 in Fedora 13

Yesterday I bought a HP Photosmart C4780. I didn't have many options because this multifunction device was the only in the shelf so my decision was obvious. However, I don't have any regrets since HP is characterized for its support to the open source community and thus it provides drivers for Linux systems, including my FC 13.

The installation procedure was almost straightforward and can be summarized in two parts, printer and scanner configuration.

The steps associated with the printer configuration were those:

1. Verify that you have installed CUPS in your Linux system
   
2. Execute the following command as root:
   yum install hplip-common hplip-gui hplip-libs hplip hpijs
   
3. Go to http://www.hplib.net and download the latest version of hplip. At this time, it is hplib-3.10.6.tar.gz. Despise you have already installed the hplib software, the required driver is not still available in your system. So untar the following files, as follows:
   tar xfz hplip-3.10.6.tar.gz hplip-3.10.6/ppd/hpijs/hp-photosmart_c4700_series-hpijs.ppd.gz hplip-3.10.6/ppd/hpcups/hp-photosmart_c4700_series.ppd.gz
   

Now, as root, run the 'run-setup' command. This program was installed during the yum procedure. This program will guide you through three basic steps. The former questions can be ignored but the last page will ask you about the driver. Select anyone of the files obtained in the step 3. Now, the wizard will ask you for restarting the cups service, do it.

Now, point your browser at http://localhost:631, add a new printer and select the "HP Photosmart C4700 series" option. Then, continue the configuration procedure as usual.
Verify that everything is ok, printing the test page :-D

For enabling the scanning procedure, I did execute the following steps:

1. yum install gnome-scan gnome-scan-libs
2. yum install libsane-hpaio

I did try "Scanner Utility" and "Simple Scan" applications from my gnome menu but none of them did the trick. So, I was looking around for a command line starting with the 'scan' word and I found it, scanimage.
Like other command line tools is not intuitive at all but its help output is, in fact, very helpful. My command line to scan a sheet is as follows:

• scanimage -d hpaio:/usb/Photosmart_C4700_series?serial=CN04HM20GK05HD > salida.png

The parameter -d hpaio:/usb/Photosmart_C4700_series?serial=CN04HM20GK05HD indicates the device that will be used for scanning. The standard output would be redirected towards a PNG file, salida.png. Now, use your regular image viewer to see the results.

Any comments please let me know.

Featured sites of the week

Welcome to this blog entry. Today, I want share some sites that I found profoundly valuable. Those sites present deep and interesting stories about culture, politics, economy, society and of course technology. Probably you know others also worth to follow sites but now I mention my favourites and frequently visited sites.

• TED, it stands for Technology, Entertainment, Design. However, TED now embraces a larger group of topics where remarkable people talk about relevant issues with deep impact in our life, today and the days to come. I can mention some singular speakers, Al Gore, Brian Greene, Bill Gates, Sergey Brin, Larry Page, Billy Graham, among others.
  
• NPR(National Public Radio), "is a producer and distributor of noncommercial news, talk and entertainment programming". I love its podcasts because they are short in time but present significant point of views that enlarge our singular point of view since they brought new perspectives about such a large amount of different topics. Today, I found other valuable asset of NPR, it not only provides podcasts but also transcripts of them which are so valuable for foreign people not only learning English but also looking for keeping informed.
  
• OpenCulture, it provides very interesting short videos about culture in general. Videos exhibited are featured videos, if you will, about music, science, movies, ideas & culture, and so on. However, OpenCulture not only focus on videos but also it regards with free courses on a variety of topics such as language, biology, computer science, economics, engineering, math, philosophy, and many more.
  
• H-Online, yesterday I found this site. It regards with open source and security topics. I'm a great fan of Linux as consequence a big fan of other open source projects. I don't have so much to say about it but I will put on eye on it and see what worthy to follow it is.

Your comments/suggestions are welcome and of course I would glad to know about your featured site(s).

Happy weekend.

First Day - Afternoon session

On the afternoon, we heard the Jose Caballero's talk. He employed an introductory presentation in which different technologies and concepts associated with Grid infrastructures were presented. He also talked a little bit about Condor which is a job manager for pool of workstations. Condor exhibits interesting features such as check pointing, resuming  and  migration of processes.
Condor can be categorized as an opportunistic job manager which harnesses idle CPU cycles found into pool of workstations. When idle work stations are found, Condor uses them for executing foreign tasks. When an 'idle' node are claimed for its owner, any process submitted by Condor is then evicted and resumed to another 'idle' workstation detected by Condor.
OSG has selected to Condor as its job manager by default.
At the end of this afternoon, for the hands-on session, we follow the instructions given here.

c u tomorrow

First Session...

Today, we held our first talk session thanks to Rob Gardner.
I have to mention that this event is been held and sponsored by different organizations and institutions such as Colciencias, Universidad de los Andes, Universidad Javeriana and OSG, of course.
In this talk, Rob gave an overview about Grid Computing and the outline of that two week workshop.
He mentioned, during the first week, we'll have many theoretical sessions given by important members of the OSG community. They'll present projects on different areas such as applications and system.
The second week will have a different emphasis, mainly directed toward practical work. As Rob mentioned, never before a practical session in which 25 'virgin' computers will become part of a grid environment has been carried out. So, that will be very exciting.

Converting ogg and m4a audio files to mp3 [Linux]

Days ago, I bought a 'mp3 device'. The nice thing about this gadget is that it is more than a mp3 player. This device can also take pictures, record audio and video, display plain files, among others. It's is very cheap, $60.oo, and now it's my partner during my daily long trips.
Today, I was setting up my device with some e-books and meditation CDs. However, I found that some audio files were with  m4a and ogg extension. I googled, how to convert from these formats  to mp3 and I found some useful thinks that I'm sharing with you.

From ogg to mp3

for file in *.ogg;do oggdec -o - "$file"|lame -h -V 4 –-vbr-new - "$(basename "$file" .ogg).mp3";done

From m4a to mp3

for i in *.m4a; do echo "Converting: ${i%.m4a}.mp3"; faad -o - "$i" | lame - "${i%.m4a}.mp3"; done

For additional short scripts, check this link http://gimpel.gi.funpic.de/wiki/index.php?title=Howto:convert_aac/mp4_to_wav/mp3/ogg_on_Linux.

PGF/TikZ and OpenSUSE 11.1

There are many Unix powerful tools that I love. Linux per-se and LaTeX.
If you're excited to present your technical ideas in a clever and elegant way, I encourage you to use LaTeX. I totally agree that PowerPoint and Impress offer a straight way to develop ordinary presentations. I mean, every one could put some bullets, add graphics, write a fancy title and so on. However, if you are interested to present a more interactive and attractive presentations, LaTeX is an important candidate.

LaTeX offers a wealth ecosystem of libraries to support the creation of elegant presentations such as:  Seminar, Propser, Beamer, and Powerdot, among others. I have not evaluated all of them but my favorite package is Beamer. This package offers interesting features for creating attractive presentations with moderate effort. Aside to those marvelous presentation packages, I found the PGF/TikZ package. It's an amazing library to create awesome diagrams, graphics and interactive presentations.

Nowadays, my laptop distro is OpenSUSE 11.1. I found it quite stable. However, OpenSUSE 11.1 comes with outdated packages for supporting the current PGF/TikZ release (2.00). Thus, I downloaded the PGF source code from sourceforge web site, but I found the installation documents very confuse.

So, I'm describing the steps that I have followed in order to enable the latest stable release of PGF/TikZ on my OpenSUSE 11.1 installment.

1. Download the PGF/TikZ source code.
2. Uncompress the downloaded file.
3. You'll get a directory named 'pgf-2.00'. Inside of this directory you'll find the following directories: context, doc, generic, latex and plain. (As well, the README file). I assumed that you have uncompressed this directory in the ~/src/ directory.
   
4. In my OpenSUSE distro, the pgf package is distributed in the following directories:
   
• /usr/share/texmf/tex/generic/pgf
• /usr/share/texmf/tex/latex/pgf
• /usr/share/texmf/tex/plain/pgf
5. Now, make a copy of these directories in a safe place.
6. Erase them.
7. Move the directories found in the recently downloaded PGF/TikZ package to the standard OpenSUSE LaTeX installation, as follows:
• mv ~/src/pgf-2.00/generic/pgf /usr/share/texmf/tex/generic/
• mv ~/src/pgf-2.00/latex/pgf /usr/share/texmf/tex/latex/
• mv ~/src/pgf-2.00/plain/pgf /usr/share/texmf/tex/plain/
8. Run the texhash command.

That's it. Now, you can test and enjoy the benefits of this powerful package (Check this link).

Good hack!