2009-07-31

Tweets of the month

Archiving teaching files, preparing for full-time research 4:25 PM Jul 31st

Cleaning up data files and folders 6:48 PM Jul 30th

VMware hacking - Setting up Windows XP virtual machine(s) 4:30 PM Jul 28th

Partition hacking - Windows Vista and Linux dual-boot 5:04 PM Jul 27th

Watching over an exam. 9:41 AM Jul 25th

A special day http://bit.ly/bWX7 14:11 PM Jul 22nd

Remembering Apollo 11 http://bit.ly/cXi5z 10:27 AM Jul 20th

Make final adjustments and prepare for landing! 6:55 PM Jul 18th

Blue planet on sight! This mission might still be worth remembering, after all ;-) 4:16 PM Jul 18th

Still not an option! 1:01 PM Jul 18th

Forget the Tolkiens, we're in Apollo XIII mode: "Failure is not an option!" 4:32 AM Jul 18th

"Christoper" still at work with "J.R.R." 9:57 PM Jul 17th

Today I feel a bit like Christoper looking at J.R.R.'s notes :-) 2:53 PM Jul 16th

The PhD proposal presentation went well! I had very good feedback from the committee. Much work ahead but looking forward to it! 5:30 PM Jul 15th

Thank you dear friends for all the support. 5:29 PM Jul 15th

Joana just gave me one more excellent idea for additional contributions. Some day soon she we will be a great adviser! 10:10 AM Jul 15th

The PhD proposal presentation is today at 15:00 GMT. I'm looking forward to it! 7:41 AM Jul 15th

Preparing written notes for the presentation. 2:43 PM Jul 14th

Pondering the use of little text and mostly visual slides... 10:55 PM Jul 13th

Preparing the PhD proposal presentation. 6:32 PM Jul 13th

The PhD proposal meeting is scheduled! It will be this Wednesday morning (US) or afternoon (Portugal). 12:26 PM Jul 13th

Good technical writing takes a long time and the time it takes is usually underestimated... I speak from my own experience... 8:28 PM Jul 11th

Reading a student's MSc thesis draft 5:04 PM Jul 11th

Answering some questions from SOD students 5:18 PM Jul 10th

Planning the SDA course project: Tough STEP 7:42 PM Jul 9th

Attending a SDA class 2:06 PM Jul 9th

Submitted the PhD Thesis Proposal to my Advisers. Awaiting comments. 3:34 PM Jul 8th

Desmontar o Magalhães / Disassembling the Magalhães http://bit.ly/Cevvl 1:44 PM Jul 7th

Full text of Benedict XVI's "Caritas in Veritate" here: http://twurl.nl/dh8wo 11:16 PM Jul 7th

Today is the day. 12:00 PM Jul 7th

Finished reviewing the "green" draft. Now I'll incorporate the changes in the document 5:42 PM Jul 6th

Just printed the latest version of my PhD proposal in green paper because I hope it is the last draft! 6:19 PM Jul 4th

Back to writing 4:13 PM Jul 4th

I failed to finish the review today. However I've made significant progress. Chapters 1, 2, and 3 are complete. Tomorrow I'll review 4. 12:16 AM Jul 3rd

Still at work! 9:01 PM Jul 2nd

Had a very nice lunch - good food (Portuguese-style grill) and good company! 1:11 PM Jul 2nd

Actually I'm only going to start the document review now. I had some emails to answer first. 10:12 AM Jul 2nd

Reviewing my latest PhD proposal draft. 9:16 AM Jul 2nd

I'm using Microsoft Visio to finalize the PhD proposal's figures. Almost done! 11:29 PM Jul 1st

Just remade one of the important figures in the proposal. Now I'm applying corrections to the text. 4:24 PM Jul 1st

SOD course discussions are (finally) over. I graded over 200 students! Now I'm back to work on my PhD. 1:52 PM Jul 1st

Idea Factory quote


An experiment is a failure only when it fails to test the hypothesis, when the data it produces don't prove anything one way or another.


The Idea Factory, Learning to think at MIT

2009-07-27

Partition hacking: installing Windows Vista and openSUSE Linux on the same machine

Once in a while a computer scientist has to install a computer. Sounds simple? Think again, especially if you want to perform a multi boot installation. In this case, the goal was to install Windows Vista and openSUSE Linux.

Here are the steps I followed:

(this procedure destroys all data in the computer so make sure you have all your data stored safely elsewhere before starting something similar)

Step 1 - Create partitions

Insert the Linux installation disc.
Restart your computer. Press key combination at start-up to boot from disc (e.g. F8).

Create the partition scheme:
(the sizes are just examples)

P1 (recovery) - NTFS - 13 GB
P2 WinVista - NTFS - 50 GB
P3 WinData - FAT32 - 500 GB
P4 Extended partition
P4.1 Linux Swap - swap - 8 GB
P4.2 Linux - ext3 - 42 GB

No need to format.

FAT32 is supported by Windows and Linux. This way the data partition can be accessed by both Windows and Linux. The drawbacks of using FAT32 are the maximum file size of 4GB and no security and extended attributes.

Take note of the device name for the Linux partition. It should be something like: /dev/sda6 or /dev/sde6.


Step 2 - Install Linux

Continue Linux installation on partition P4.2.

After installation, the MBR is loaded with GRUB.


Step 3 - Install Windows Vista

Insert the Windows installation disc.
Restart your computer. Press key combination at start-up to boot from disc (e.g. F8).

Install Windows on partition P2.

After the installation, GRUB is replaced in the MBR with Windows Boot Manager. This means that it is no longer possible to boot Linux.

Reboot.

Install drivers.
Run Windows Update until there are no more updates available. It is normal to have a large number of updates.


Step 4 - Restore GRUB

Insert the Linux installation disc.
Restart your computer. Press key combination at start-up to boot from disc (e.g. F8).

Choose the "Rescue mode" option and choose the 'root' user.

Rescue> mount /dev/sda6 /mnt

Rescue> grub

grub> find /boot/grub/stage1
(hd0,5)

grub> root (hd0,5)

grub> setup (hd0)

grub> quit

Rescue> reboot

Restart - GRUB should be back in control of the booting process.

If you wish to change the GRUB menu, just edit the /boot/grub/menu.lst file using Linux.

If at any time you need to restore Windows Boot Manager (for a Windows Service Pack installation, for instance), you can use the free tool EasyBCD.


--

Good luck with your installations!

2009-07-24

Idea Factory quote


The steps in the scientific method are: (1) statement of the problem; (2) hypotheses as to the cause of the problem; (3) experiments designed to test each hypothesis; (4) predicted results of the experiments; (5) observed results of the experiments; and (6) conclusions from the results of the experiments.


The Idea Factory, Learning to think at MIT

2009-07-22

Home

Home



A visually spectacular movie about very important and pressing environmental issues.
You can watch the trailer on YouTube.

It does a good job of presenting the problem, but not so good at proposing solutions. How can we make the transition from an oil-based economy to a more sustainable alternative where people have jobs and can earn their living?

If you are interested in the subject I suggest you read the book "Hot, Flat, and Crowded".

P.S. - This movie clearly benefits from High Definition movie format, like Blu-Ray.

Amor / Love

O amor não consiste em olhar apaixonadamente um para o outro, mas em olharmos juntos na mesma direcção.



/ This post is bilingual: Portuguese (Portugal) and English (U.S.) /

Love is not about looking passionately at each other, but is about looking together in the same direction.

For my princess...



Happy anniversary!

2009-07-21

Harry Potter and the Half-Blood Prince

Harry Potter and the Half-Blood Prince

Albus Dumbledore: You must be wondering why I brought you here.
Harry Potter: Actually sir, after all these years I just sort of go with it.

Teacher warnings

You spend half the time warning about something wrong that half the people end up doing!


Or like the poet said "Words are gone with the wind!..." / "Palavras, leva-as o vento!..." ;-)

2009-07-20

Physical limitations of Distributed Systems

(...) Engineers should be aware of some of the fundamental limitations they face when developing (...) distributed applications — in particular, the finite speed of light.


"Fighting Physics: A Tough Battle" by Jonathan M. Smith in "Communications of the ACM", July 2009

Perfect design

It's very hard to find that [perfect] design point, but it’s very satisfying. It’s a lot like mathematics because you’re looking for the elegant solution


Barbara Liskov in "Communications of the ACM", July 2009

Apollo XI

Remembering the great Apollo XI feat of 40 years ago, here is a very good photo collection.


By the way, did you know that most Astronauts are Engineers? ;-)

2009-07-17

Idea Factory quote


At Oxford and Cambridge there are no classes; instead students meets regularly with tutors. I wished MIT encouraged more of this, but it's very time-consuming for the professor, and if he spends his time teaching and explaining things, there won't be time for the real work of bringing in research funds, consulting, publishing and delivering papers, making a name for oneself. Besides, if you can't figure out everything by yourself, you probably don't belong at MIT.


The Idea Factory, Learning to think at MIT

2009-07-15

Private tweeting

Everybody has a busy schedule these days, and scheduling meetings just for sharing the latest updates is not very efficient, although nothing replaces eye-to-eye contact.

A possible way to keep a loosely coupled team in context would be to use Twitter, but you probably don't want to expose sensitive business information through a public service with no strong privacy assurances.



One way to "emulate" Twitter would be a mailing list where only the email subject would be used, or a Google Group, or ...

Do you have any ideas about this? Do know any free implementation of simple, small-scale, Twitter-like application? If you do, please leave a comment.

Time to dive

You should focus as soon as possible, and "diving into the ocean" is the best way to do it!

SS


Hypothesis

A hypothesis consists either of a suggested explanation for an observable phenomenon or of a reasoned proposal predicting a possible causal correlation among multiple phenomena.

(...)

The scientific method requires that one can test a scientific hypothesis. Scientists generally base such hypotheses on previous observations or on extensions of scientific theories.

(...)

A hypothesis is never to be stated as a question, but always as a statement with an explanation following it. It is not to be a question because it states what the experimenter thinks will occur. Hypotheses are usually written in the "if-then form": If X, then Y.

Source: Wikipedia

2009-07-13

Assure vs. Ensure vs. Insure

Assure vs. Ensure vs. Insure

Basically, the words assure, ensure and insure all mean the same thing: to guarantee or to promise that something is true or that something will happen. But there are slight differences between them:

Assure means to say or write the guarantee:
He assured me that the product would be delivered tomorrow.

Ensure means to do something to make sure or guarantee that something happens:
A firewall helps to ensure that hackers don't attack your PC.

Insure means to guarantee something with insurance or other financial instruments:
In most countries you need to insure your car against accidents.


Note that we use the infinitive "to" before each of these words.

Source: English in Focus

2009-07-12

Chestnut: Hero of Central Park

Chestnut: Hero of Central Park


Sal: [after finding a puppy] I'm going to call him chestnut because he's little and brown.

2009-07-10

Idea Factory quote


IASE is one of the mechanisms by which MIT maintains its close links to industry. Mid- to upper-level engineers or research and development managers come to MIT, take a few classes, maybe do a small project, meet a lot of professors, and later hire the professors they meet as consultants to figure out how to solve their problems.


The Idea Factory, Learning to think at MIT

2009-07-09

IST circa 1944 (brand new)


Read more about Instituto Superior Técnico.

My cloud

Wouldn't it be useful if we could easily setup and connect a computer to the Internet and have it support a private cloud with collaboration applications for instant-messaging, email, document editing, etc?

In my opinion, one of the problems with current cloud computing is that you have to rely on a trusted third party to keep your data safe and secure. In most cases, trust is based only on a leap of faith. But what about critical applications? Would you trust your keys to Google/Yahoo/Microsoft/Amazon/etc?

2009-07-07

Desmontar o Magalhães / Disassembling the Magalhães

A edição da revista Exame que está agora nas bancas contém um artigo muito interessante (reproduzido parcialmente aqui), onde se desmonta o portátil Magalhães e se identifica a origem dos componentes do "primeiro portátil português".

Penso que este pequeno computador foi uma iniciativa importante mas que cometeu erros graves. O principal, na minha opinião, foi apostar-se num portátil e não numa plataforma, que pudesse ser instalada em qualquer portátil Intel Classmate ou outro, como o OLPC. O valor acrescentado de um portátil destes, para crianças, está nos conteúdos e não no equipamento em si.


/ This post is bilingual: Portuguese (Portugal) and English (U.S.) /

This month's edition of Exame magazine has a very interesting article (partially available here, in Portuguese), where the Magalhães laptop is disassembled and the origin of the components in the "first Portuguese laptop" is identified.

This small computer was an important initiative but committed serious mistakes. The main error, in my opinion, was the bet on a laptop instead of a platform, that could have been installed on any Intel Classmate, but also on the OLPC. The added value in a laptop like this, for children, is in the contents and not in the hardware.

2009-07-06

May vs Might

Use might when the outcome is uncertain or unlikely and use may when something is more likely to happen

There are two exceptions to this rule:
- Might is the past tense of May
- Use Might when talking about something not happening because May could mean asking permission

Source: Grammar Girl

Google tips for webpage design

Here are four design tips from Google to pay attention to:

Tip #1: Pass the 8 second test. At first glance, a visitor should understand the purpose of your website within a few seconds. People are busy and have limited attention spans — you want to keep them from hitting the dreaded back button.

Tip #2: Tell them what's in it for them. Create clear and tangible benefits (e.g., "Save more! Make extra money! Look better with our product!").

Tip #3: Use compelling images. Try product images instead of generic stock photos, icons with blocks of text, and buttons instead of links. Keep in mind that a low-quality, irrelevant image can kill your site's credibility.

Tip #4: Close the sale. Help your visitors take the next step. Make that step clear and easy to reach; don't make them hunt for it. Action words like "buy now" may work better than "add to cart," for instance.

Originally posted on the Google Blog.

2009-07-04

The Emperor's Club

The Emperor's Club
Prof. William Hundert: The worth of a life is not determined by a single failure or a solitary success.

O tripé da vida cristã / The tripod of Christian life

A certeza da pertença à Igreja;
O espaço da oração e do silêncio na vida interior;
Não ter vergonha do Evangelho.

Pe. Duarte da Cunha



/ This post is bilingual: Portuguese (Portugal) and English (U.S.) /

The certainty of belonging to the Church;
Room for prayer and silence in our inner life;
Do not be ashamed of the Gospel.

Fr. Duarte da Cunha


P.S. - Parabéns e obrigado Padre Duarte, pelos 16 anos de sacerdócio! / Congratulations and thank you Father Duarte, for 16 years of priesthood!

Image credits

No to SQL

It appears there is a "rebellion" against relational databases, as reported in Computer World.

This is the typical problem when you just use off-the-shelf software without considering other options.

Some years ago, Prof. PMMVAS, in a class, presented a good summarization of the trade-offs in the database world:

Data structure complexity VS Query capabilities

Relational databases have simple data structures (tables) but sophisticated querying capabilities (SQL SELECT).

Hierarchical databases (e.g. XML) have more complex data structures (records) and less powerful queries.

Object databases have complex data structures (object graphs, code+data encapsulation) but poor querying capabilities.


It is an interesting discussion on how to keep our digital "bookshelves" organized...

2009-07-03

Idea Factory quote


In engineering the product is the proof of your honesty.


The Idea Factory, Learning to think at MIT