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Tuesday, August 20 2013

Aspie-Quiz Graph modified

People, especially people with Asperger Syndrome, have expressed their interest in the test and graph found at the Aspie-quiz web page.
The test seems to be part  of one research work and it adds to the graph info about the autistic and neurotypical hunting variables. Some people think that values aren't accepted or used enough and they dislike the graph.
I think it's sad to loose interest of one part of the public because of that detail.  Some people asked for one version of the graph without that and I decided to do it myself in order to give people what they want and help the research to have more participation. This is what you get:

What must i do to have my own graph?
  1. First you must do this test. If you are really interested it's a good idea to log in so they can track your evolution (anonymous but logged) for the research.
  2. At the end of the test you will have one graphic and one url to retrieve it in case you loose the image. Like this one: http://www.rdos.net/eng/poly12c.php?p1=82&p2=78&p3=67&p4=68&p5=50&p6=65&p7=58&p8=57&p9=41&p10=44&p11=88&p12=53
  3. Copy all the string starting with the question mark and add it to this one: http://www.saberlibre.net/g/nt-aspie-graph.php
  4. You will have something like this: http://www.saberlibre.net/g/nt-aspie-graph.php?p1=82&p2=78&p3=67&p4=68&p5=50&p6=65&p7=58&p8=57&p9=41&p10=44&p11=88&p12=53.
You will have the new image if your browser go to that url.
Please, if you find any error, report it to me. I'll fix it.

Saturday, June 22 2013

Help to spread this video, please

Please help to spread this video made by a american jewish  women that visited Palestina.

Sunday, January 13 2013

Changing the Background Image back.jpg of gfxboot Version of grub

using 'vimdiff' to compare the output of 'identify -verbose xxx.jpg' True, grub 0.97 is old. But its configuration is much easier (than grub2) for me to understand and it can be easily installed into a separate partition independent of the OS. I used to use the grub-legacy version (referring to debian package names here) but it only supports background images of 14 colors. Recently I installed antix and finally figured out how to change the background image of the grub-gfxboot version.

Basically I followed instructions in the pclinuxos wiki or SimplyMepis wiki (my desktop linux!) and still couldn't get grub-gfxboot to recognize the new image -- even if I just slightly modified the original back.jpg in gimp and exported it again. Finally I used the identify command of the imagemagick package (with "-verbose" option) to dump the information about the slightly modified version and the original version, and figured out the correct conversion command (using the convert command of imagemagick):

    convert -resize 800 -colors 255 -quality 80 -interlace none -sampling-factor 2x2 your_customized.jpg back.jpg

(In the vimdiff picture I removed some unimportant portions such as channel statistics.) Note that I reduced the quality to save space. since the image has only 255 colors. And yet it already looks so much better than the 14-color background that I feel like staying at and admiring the new boot loader image :-)

Tuesday, April 17 2012

Back to the City of Dreaming Spires for a DPhil

This September I will be going back to Oxford to do a DPhil. I will study the appearance of critical mass in budding on-line political communities.

Online communities can greatly impact society, as the recent events in the Middle East, and the rise of global online social movements such as Occupy Wallstreet, suggest. But in order to thrive, and become a community at all, online communities have to attain a critical mass of initial users. The central problem of which is that until a certain number of participants are present, joining the community is not going to affect outcomes, or be socially rewarding to newcomers.

Also, more in general, the exact factors that determine growth in the early stages of online communities, are still ill understood. Even internet giant Google has failed to attain critical mass for some of its platforms, such as Google Wave.

For my DPhil I will contrast budding political communities that turn out to become successful (grow or continue to exist) with those that fail. More specifically, it will be examined whether the founders and early participants of successful online political communities, differ, either individually or in their position in social networks, or whether it are the early communities as a whole that differ, for example in community-level dynamics.

Contrary to the traditional belief in the impact of leaders, the answer to this question is not a given, as studies of `leaderless’ online movements, and smart-mobs, suggest. Also, several theories suggest the possibility that founders of successful communities could be socially indistinguishable from those of communities that fail. See my full proposal for more information.

I have a scholarship from the Economic and Social Research Council, and will be doing my DPhil at the Oxford Internet Institute, where I also did my masters. The OII is an interdisciplinary research-centre of the the University of Oxford, focusing on Social Science research applied to the Internet. I will be leaving a great job at a great startup for this, but then one sometimes has to make difficult decisions in order to pursue a dream: that of doing (great and relevant) research, and becoming an academic.

Panorama of Oxford, and the entrance to 1 St Giles, where the Oxford Internet Institute is based

Academia.edu in San Francisco

While still working on my MSc thesis, I went to San Francisco this summer. I first attended the Digital Humanities 2011 conference at Stanford University. It was great to see many known faces there again, and the talks and posters were ‘not bad’ either. Especially impressive was the keynote on Culturomics, the quantitative analysis of culture using millions of digitized books.

Then I started work at Academia.edu, a funded startup which now has over a million users. Academia.edu is a social network for scholars, which – besides the usual social network-features – organizes people by their department and research-interests, and enables scholars to present their publications in a beautiful way. Not only does it allow direct subscription to the news-feed of individual researchers (as in a personalized journal), but it also makes uploaded papers more widely available, as user-pages are indexed by Google, and thus easy to find by researchers and other interested parties.

Academia.edu is (soon was, see next post) a great place to work. The team consists of great engineers, and decisions are generally made in a non-hierarchical way that allows the best ideas to come to the fore. A lot of interesting new technologies are being used as well, such as Redis, MongoDB, Memcached, Varnish, and Solr (besides Ruby on Rails). In that sense it is a real startup. And since I arrived we have started doing automated testing, and been improving the quality of the code. In addition to all this, our office also provides a very nice work-environment, as it is centrally located (Kearny and Bush), with a lot of light, and plants (for whoever wants them on their desk).

My work-space at Academia.edu

Our elephant-ear – name says it all – plant in the office at Academia.edu

And finally, San Francisco is not only part of the Sillicon Valley area; the heartland of the internet, but also is a great place to live. Though there is a bit more fog than I initially expected. My room is near Golden Gate Park, which is nice for taking long walks, and being surrounded by nature. Besides, there are a lot of cool coding-related events in the city (almost daily), many theaters, museums, and there are even some nice beaches nearby (Ocean Beach is my favorite, though the sea there is very cold). I haven’t gone for trips outside the city that much, but I did visit Lake Tahoe twice, which is a real gem, both in summer, and in winter.

Tahoe in the middle of summer, 2011

Tahoe during our company ski trip

Thursday, December 15 2011

Dr. Geo: hacker spirit in a candy box

When you teach mathematics at secondary schools, you enjoy using interactive geometry software with your students. Dr.Geo is one such free software, but it comes with some unique features. With such software, students learn geometry the way it should be learned -- by drawing, but Dr. Geo goes one step further.

Dr. Geo has a long tradition on GNU/Linux. It was the first software of this category since 1999. Beginning 20xx, it plays nicely on Windows and Mac OSX as well.

In fact Dr. Geo bundle is now distributed as an universal portable application. This means student Bob can use the software on his usb key on the school's Mac OSX, then continue working on an Internet coffee's GNU/Linux workstation, then finish his work at home on his Windows PC. Each time, the same portable app is used. Moreover, when suddenly interrupted, Bob can save the session of his work - like a memory dump - to continue later, on a different workstation or system.

This is true both for interactive geometry activities and programmed geometry sketches. The later feature is a nice extension, an API, to design programmed geometry sketch. Of course the resulting sketches are all interactive. Read this small example. Programming is also available in interactive sketch, the user can plug small scripts in the canvas to do specific computation, for example to compute a curve and a tangent line at an arbitrary position.

Therefore, advanced teachers/students will appreciate the fact that scripting is more like writing math formulas than writing low level programs (no need to do a lot of initialization, for example). To draw an interactive segment and a bissector, you write:

drgeo := DrGeoCanvas new.
s1 := drgeo segment: 0@0 to: 5@5.
drgeo perpendicular: s1 at: (drgeo middleOf: s1).

Last but not least, free software spirit is so much at the heart of Dr. Geo -- you can study, modify and distribute its source code from itself.

Yes! You can modify Dr. Geo from Dr. Geo!

All in all, Dr. Geo is a hacker spirit in a candy box: young learners enjoy using it, when they grow up they can dig in programming and even learn from the Dr. Geo own design.

All pure fun.

Friday, November 18 2011

3D Cube section

You can produce pseudo 3D figure. A friend sent me this example: the section of a cube by a plane.

In this sketch, the author plays with the transparency of several overlapping polygons to emphasis the 3D perception.


Saturday, November 12 2011

English video tutorial

Video tutorials are funs for three reasons:

  • it is efficient for the user both in term of relevance and time to get to the point
  • it is easy to produce and not time consuming for the producer
  • it is easy to distribute through the video server. DailyMotion even supports upload and conversion from Ogg/Theora video!

For theses reasons I am producing DrGeo video tutorials with English spoken comments, be nice with me, English is not my native language.

Visit DrGeo group@Dailymotion

Saturday, November 5 2011

Conic Sections


Alain Busser presents us a nice tutorial to build conic sections with Dr. Geo. He also proposes a macro-construction of this resulting work.

Read his tutorial

Wednesday, November 2 2011

DrGeoII pre-release 11.12b

A few changes based on user requests:

  • circle can be constructed by center and segment
  • added back the intersection tool. You have now two options to construct intersection:
    • as before, on the fly, when constructing a line, you can construct the intersection
    • by selecting two lines, you need to access the new intersection tool in the Point menu or toolbar.


The changes are in pre-release 11.12b.

From your latest DrGeo installation, you can upgrade to DrGeo pre-release 11.12b. To upgrate to latest release, select in the DrGeo environment menu "update DrGeo", then save the session to make the changes permanent.

Friday, October 28 2011

Huge sketch

Xavi de Blas sent me this sketch to calculate a body gravity center. The file is huge and I will include it in the next Dr.Geo 11.12 release.

The resulting sketch: Centro-de-gravedad1.png

The sketch with the hidden constructions: Centro-de-gravedad2.png

Getting the property tool back

After an user request, I just added back in DrGeoII the item property tool.

With this tool you can edit:

  • the coordinates of a free point on the plane
  • the curvilinear abscissa of a point free on a curve, the abscissa belongs to [0 ; 1]
  • a free value
  • a script

In the later case, DrGeo opens a tiny Smalltalk browser to study and to modify the code. When modifying and saving the code, the canvas is automatically updated. Underneath, the script code is recompiled, thanks to the Smalltalk machinery.

All but the script operation are backed in the command machinery of DrGeo, so you can undo/redo.

Un script avec deux arguments

Wednesday, October 12 2011


Monday, October 10 2011

Consumers Don't Own Computers "Designed for Windows 8", and They Go to Landfills Earlier (Side Effects of "Trusted Computing")

Some computer manufacturers will force you
to "trust" Windows 8 only, disallowing you to
do usb-booting or cdrom-booting of other operating systems Microsoft Windows 8 alpha is released and downloadable. But no, I am not recommending it. Nor am I denouncing it in favor of GNU/Linux (well, not in this article anyway). What you should be aware of and concerned about as a consumer is those machines labeled as "Designed for Windows 8". Much more so if you care about the environmental and humanitarian problems caused by e-wastes, for these machines do end up much earlier as e-wastes than the ordinary machines manufactured now.

Machines labeled as "Designed for Windows 8" have to support UEFI。 UEFI is said to have many nice features, which I am not knowledgeable about and will not discuss. But I can assure you that one of those features is a downright hoax, scam, and lie. The "secure boot" feature in UEFI is claimed to make your computer more secure by disallowing intrusions from untrusted sources. This and certain other features in UEFI are important elements of Trusted Computing, a mechanism advocated by Microsoft and other big IT companies. The claim is that booting a computer from an untrusted source (such as a tux usb key which has applications in tourism, education, environment preservation, LOHAS, and ethics) is a security threat and should be avoided.

There is just one tiny problem: it's not you, the consumer, who gets to decide who is to trust. The propaganda claims that the consumers are too dumb (well, ok, actually phrased in a much more polite way.) to make their own decisions about whom to trust. ("Microsoft or Chao-Kuei?") Software booting from an untrusted source may contain rootkit, for example, which would gain absolute control of your computer. The real, unsaid intention, however, is to prevent consumers from using alternative players and readers on alternative operating systems to circumvent the human-right infringing and infamous Digital Rights Management. If the big IT companies let you decide whom to trust, then they cannot trust you as a DRM-abiding consumer. With the secure booting mechanism in UEFI, the IT companies finally can trust that you will not be able to ask your computer to do what is best in your interest, for example exercising your fair use right and other rights requested in the digital consumer bill of right.

Ironically, history shows that one of the most famous rootkit invasions was not performed by individual bloggers and GNU/Linux lovers like me who have to build reader trust by behaving well and telling truth, but rather by big companies who can repeatedly abuse consumers and yet successfully keep them buying. In 2005, Sony BMG invaded consumer computers. The lovely music CD that consumers buy play nicely in CD players or DVD players. But it hijacks your Windows if you play it on a Windows computer. This creepy behavior was exposed on the Internet and caused protests. Sony BMG's Global Digital Business President responded, "Most people, I think, don't even know what a rootkit is, so why should they care about it?" But the most interesting part is the reactions of Microsoft and Anti-virus companies. What would you do if you were Microsoft and if Sony invaded your customers' computer? I would definitely provide security update and then also advise against buying these CD's or even sue Sony, depending on how nice I wanted to be with Sony. But Microsoft did nothing for several months. Nor did most big-name anti-virus companies. These are the companies who take your money, vouch to "make your computer more secure", and assure you that you can "trust" them.

Even more ironical is the ensuing fairuse4wm event in 2006, in which Microsoft behaved exactly the opposite. The newly upgraded windows media player employed DRM measures and suddenly deprived users of their backup right. Someone with the ID of viodentia wrote and shared on the Internet a piece of software called fairuse4wm to restore the users fair use rights. This time Microsoft swiftly produced "security updates" to disable fairuse4wm within 10 days. Viodentia updated fairuse4wm to circumvent Microsoft's updates, and Microsoft produced further security updates to disable it, ... and so on. Whom do Microsoft's "security updates" serve and which of viodentia and Microsoft is more trust-worthy?

From DRM to Trusted Computing to DMCA anti-circumvention History has shown that some of the big IT companies unitedly decided not to trust you. So who would you, consumer, trust? Oh, I am sorry. I should not address this question to you, for it is not you who get to choose whom to trust. I should ask computer manufacturers who enforce trusted computing for you. And for sure we all know that Microsoft is the only party for any consumer to place trust in -- according to the manufacturers. "We decide for you whom to trust." That's the real meaning of trusted computing. And the "secure boot" feature of UEFI, which is "Designed for Windows 8", is one of its pieces. To learn more about trusted computing, you can read the EFF article. My article "DRM and Other Forces Overriding the Three Laws of Robotics" ( English, French, Spanish), my paper "1984 in the Making: Stealthy Invasion of Consumer Rights and Privacy by ICT Corporations" and my novelette in Chinese explain the relationship among DRM, Trusted Computing, and DMCA. It's also summarized in the picture to the right. Search for "windows 8 linux" for recent controversy about Microsoft enforcing UEFI on manufacturers.

To be more precise, it is not true that secure boot precludes other operating systems in principle. If the hardware manufacturer is willing to certify some minor OS, this lucky minor OS can also boot from a "designed for windows 8" computer. Still, the decision is for the hardware manufacture, not you, to make. Finally, some manufacturers may decide to allow the buyers to optionally disable the secure boot feature of UEFI. It is this last category of future computers that we will recommend everyone to buy -- not only because you would want to be a wise consumer but also because it prevents worsening of the environmental and humanitarian problems caused by e-wastes.

As explained in the e-waste part of the censored 4-part iPhone game "phone story", the discarded electronics either end up in landfills or exported to developing countries for "recycling", which in fact employ methods that are harmful to both human health and the environment. Unfortunately the business strategy of planned obsolescence meant to increase the profits of the big IT companies further intensifies this process at the extra cost of the planet and its inhabitants. It's bad enough when phone companies pursue their profits with little regard to the planet, but it adds insults to injury when the computer manufacturers do this without even really increasing their own profits.

You see, you may not care about GNU/Linux, but people like Helios devoted to refurbishing recycled computers for the disadvantaged choose GNU/Linux over outdated or pirated Windows for good reasons -- it makes the recycled computers greener, cleaner, more Ethical, and more educational. With manufacturer-enforced secure boot, these computers would go to the landfills or "recycling" centers instead of going to the disadvantaged because Helios and other people who care would not be allowed to install GNU/Linux for them. And the hardware manufacturers don't even make more money because of these extra, unnecessary harms done to the disadvantaged and to the planet, if profit-making is ever a justifiable excuse for irresponsible manufacturing behaviors! These disadvantaged people are not going to buy new computers because they cannot get refurbished computers.

What can you do to help? Grab (perhaps with the help of you Linux friend) some live Linux CD from distrowatch, and maybe additionally create a live usb from it. Demand to boot the live CD or live usb before purchasing your next computer. Make sure that it is some minor Linux distribution, not just the store-suggested Linux distribution, that successfully boots. It's not about denouncing big brand Linux versions. It's about making sure that you get to decide whom to trust your computer security to. Show the computer guys in the store this article if necessary and insist on buying a computer that allow the buyers to disable the secure boot feature of UEFI. You don't need to love or use or even learn GNU/Linux if software freedom do not appeal to you. You can simply use it as a tool for testing the computer and discard it afterwards (though it would be a pity). Please do this for the planet, for the disadvantaged, for the society, if not for yourself as a wise consumer who knows to claim his/her full ownership of the purchased computer and basic user rights.

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