Blog posting resumed

"AFJ's PhD" blog was created in November 2004 to report on-line the status of my PhD work. After finishing his PhD in July 2009, the posting was suspended. However, after several requests, I decided to reactivate the blog. The renewed "AFJ's PhD and after" blog will provide information on my work as a researcher in INESC-ID and my activities as a Assistant Professor at IST/TULisbon.

DONE!!!

It was more than a month ago, but just now I had time to post here the announcement: my PhD thesis defense went very good. I finally got my PhD. It is done!

Tomorrow is the "D" Day

Yep, is tomorrow. The "D" (from defense - PhD thesis defense) day is coming fast. For more info take a look at official announcement.

LaTeX: Keeping capitals in bibliography

The bibtex was removing capital letters from paper reference that I wanted to keep. It took me a little bit to figure out a solution. But I think it might be useful, so I post it below. First I present the original bibtex entry:

@INPROCEEDINGS{

(...)
TITLE = "ION Framework - A Simulation Environment for Worlds with Virtual Agent",
(...)
}

The result was:

(...) Ion framework - A simulation environment for worlds with virtual agents (...)

The solution was to add brackets to the field as shown below:


@INPROCEEDINGS{
(...)
TITLE = "{ION Framework - A Simulation Environment for Worlds with Virtual Agent}",
(...)
}

And it worked fine:

(...) ION framework - A simulation environment for worlds with virtual agents (...)

Draft submitted!

Finally the final draft of my PhD thesis was submitted. Now the jury will review it and, based on their comments, I will prepare the final version. If everything runs smoothly, the thesis defense should be in next July.

The importance of a good adviser...

After a long time wandering among several charts to represent some experimental data, I was completely stuck. None depicts the data clearly, neither illustrates the idea I want to transmit. When I was almost giving up and using an awful 3D chart, my adviser comes to see what I was doing, while drinking his after-lunch coffee and in a glimpse just solves my problem. "Do not complicate. Use two 2D charts!" - he said. Obviously he was right. Simple solution.

"Damn! Why didn't I think about that before? "

Anyway, it worked fine and the two charts below express well what I intend.

Shape pool statistics tool

To help me while analysing the behaviour of the shape pool produced by the CAS/HFP decomposition algorithm, I developed a small tool. This tool, whose screenshot is depicted below, compares two shape pools and provides important information about them.

Screenshot of shape pool statistics tool

Web page with PhD work

I don't know why I took so much time to create a web page about my PhD research. However, it's better late than never, so I have just created one. It's not complete, but it is a beginning.

Visit the web page of my PhD research, which focused on Thesaurus-based 3D Shape Retrieval, T-b3DR for short. There you can find some information about my work and a couple of useful prototypes.

LaTeX equation editor

I've been using a very useful tool for writing equations in LaTeX. Although it is quite easy to found on the internet, I notice that some of my colleagues did not know about it. Thus, I thought it might be a good idea to publicise it here.

So, if you're using LaTeX you should give a look at the LaTeX equation editor. It is simple, fast, and accurate. And you do not need to install anything, it runs on your web browser.

Writing a number set in LaTeX

I needed to write the formal notation of a multi-dimensional dataset in my PhD dissertation. Since I'm using LaTeX and this dataset consists on a real number set I just have to use the mathbb font, provided by amsfonts or amssymb packages.

Thus, providing that the proper packages were included in the preamble of the document, I just had to use, in math mode:

\mathbb{R}^n

to obtain:

Random Number Generator

During my tests I often needed to produce some random numbers. Sometimes, when the occasion does not justify more worries, I used a very useful site developed by Mads Haahr of the School of Computer Science and Statistics at Trinity College, Dublin in Ireland. The RANDOM.ORG produces true random numbers and has been a useful help. It seems that it is now turning into a commercial site but I hope it remains free, at least for the basic features.

Feature vector distances between similar shapes

While writing the PhD dissertation I need to depict some data I gathered during my research. One example regards the distances measured between spherical harmonics feature vectors of similar 3D shapes. In the last couple of days I've been working on this, producing results such as the depicted below.

Distances between SHA feature vectors for a set of similar shapes.

Chart depicting the distances of top 5 similar shapes on ESB collection

Prototypes working on Linux

Although developed aiming a cross-platform solution, the prototypes of my PhD research only have been compiled in Windows. Until now. Moved by the need of having my prototypes running on a Linux system, I dedicated a few hours to creating a makefile and making some slight changes in the code in order to compile the prototypes in Linux. It worked fine! Now I have my prototypes running in both Windows and Linux!

Spherical Harmonics Visual Representation

Although I had developed most of the code in the last year, just today I assembled all together in order to create a prototype that produces visual representations of spherical harmonics (SHA) signatures. The SHaVisRep prototype receives as input the binary signature created by the the executable for computing SHA representations provided by Kazhdan and produce a visual representation for this descriptor. This visual representation can be a 3D column chart or a 2D line chart in VRML or BMP format, respectively. The Win32 version of the prototype is avaliable for download [ZIP 110KB].

Ant 3D model
___

Shperical harmonics of ant 3D model, represented as a 3D column chart
___

Shperical harmonics of ant 3D model, represented as a 2D line chart

Prototype packages

The prototype developed during my PhD research is divided into four distinct applications: CASDecomposer; Segment Clustering; ThesaurusBuilder; and ShapeRetriever. These are simple console applications that allow the user to control the algorithms behaviour. However, instead of independent applications, the whole prototype is composed by a set packages presented below.

Prototype packages (click on image to enlarge)

The 3D shape thesaurus

Those who have been following my PhD work know that one of the main contributions of my research is the development of a 3D shape thesaurus. However, despite some previous efforts, I had never been able to clearly illustrate this concept in a diagram. Until yesterday. Thanks to a welcomed inspiration I created a very good (i.m.h.o.) diagram to represent a 3D shape thesaurus. Of course it is almost meaningless without proper context (you will find it in my thesis) , but I'm so keen about this diagram that I can't resist to publish it right now.

Schematic representation of a 3D shape thesaurus

Eurtooling21 project concluded.

The Eurotooling21 project has just come to the end. As part of our participation in this EC funded project, we developed the Quick Quotation Assistant (QiQA) tool. Noticeably, the QiQA was selected as one of the Top 10 results of this project that comprises 33 partners from ten EU member states. Detailed information on this tool can found at the QiQA's final technical report.

Filipa and Tiago Wedding

Last weekend my colleague and office mate, Tiago Guerreiro, got married. We attended the wedding and subsequent reception. It was a nice ceremony at the church followed by a phenomenal event at the "Pousada de Palmela", as you can check in the picture below.

One of the highlights of any wedding: throwing the bouquet... and the girls disputing for it!

Just kidding. No girl fighting! Unfortunately! Eh eh eh... But the party was awesome and went on till very late night (or early morning, to be more correct).

I published more pictures of this event on a Picasa Web Album. Feel free to take a look.

Clustering Reader

As part of my PhD research I needed to cluster the the shape segments according to its spherical harmonics signature. After accomplishing this step I want to easily "see" the results and create a directory tree filled according to a given partition (I compute four different ones). To that end, I developed "Clustering Reader" a simple Windows applications that reads the XML file produced by the clustrering algorithm, shows the computed partitions and distributes the corresponding segments (VRML files) by the corresponding directories.

Screenshot of Clustering Reader

QiQA idea overview

While preparing the Quick Quotation Assistant (QiQA) final report, within my collaboration on Eurotooling21 project, I redesign from scratch the diagram that represents the idea behind this tool. Below you can find the new diagram, depicting the basic principles of the quotation assistance environment.