ECG IIR Notch Filtering Using Transient Suppression

Recently, I was going through my undergraduate lecture notes. I stumbled upon an exercise which I found interesting. The task consisted in implementing the algorithm proposed by Pei and Tseng, which uses vector projection to minimize the problem of transient values when applying an IIR notch filter to an ECG signal.

Top: original ECG signal with AC interference noise. Middle: filtered ECG signal using a typical IIR notch filter. Bottom: filtered ECG signal using an IIR notch filter with the proposed transient suppression technique.

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Installing LaTeX

Recently, quite a few friends have been finishing their degrees and preparing their final theses. A very common struggle was the actual procedure of writing the thesis document. I don’t mean sitting down and writing the content (which is already quite challenging itself), but to manage big amounts of text, figures, and (specially) references efficiently. Being such a big fan of LaTeX myself, I always recommend it. However, setting up everything for the first time might not be very intuitive for everyone, since it requires a few steps. Therefore, I decided to write this small guide on how to setup LaTeX in your computer for the first time.

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Fixing Unstable WiFi Connection in Windows 8

I just upgraded my old laptop to a new one with Windows 8.1 installed. Putting aside the small details of getting used to a new operating system (OS), I found something that was terribly annoying

Apparently, there is an awful issue with Windows 8.1 management of the wireless adapter. This translates into an unstable, limited WiFi connection. I immediately jumped into the internet, trying to find a solution. Surprisingly, this was a very common issue. Nevertheless, it took me quite a few tries to finally fix it. If you find yourself in the same situation, I recommend you to try the following options (in this order):

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Generating a Binary Mask

When working with images, selecting a specific region of an image to work with is quite common. Therefore I made a script that allows you to generate a mask with one or more regions of interest (ROIs). The shape of the ROIs can be rectangular, elliptic, (irregular) polygon, or free-hand drawn.

Original Lena, generated mask, and masked Lena.

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Using jphysicsB.bst with Titles in LaTeX

Recently, I was working on a paper submission. Being a huge fan of it, I used LaTeX for the manuscript preparation. The journal’s guidelines for submission indicate that LaTeX Harvard Alphabetic Style must be used together with the BibTeX style file jphysicsB.bst. The guidelines also instruct that references must include the title of the article/book/etc. However, the jphysicsB style does not print it (this is not an error, that is the way it is supposed to work). How to solve this?

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National Instruments University Challenge 2009

Last week, we obtained the First National Prize in the National Instruments University Challenge 2009 with the project Home Control System for Handicapped People based on Electrooculography. It was a very challenging but also very rewarding experience for all of us in the team: Luis E. Lara-Gonzalez, my colleague and friend, and Prof. Jorge A. Martínez-Alarcon, M. Sc., our professor and advisor.

From left to right: Diana González-Ramírez (NI Marketing Coordinator), Luis E. Lara-González (colleague and friend), yours truly, and Arturo Vargas-Mercado (NI Academic Program Manager).

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Social Service at HRAE Oaxaca

In Mexico, in order to complete the credit requirements of any undergraduate program, you are required (by law) to perform a so-called social service: 480 hours of non-remunerated work in a nonprofit organization (preferentially in your field). This time corresponds to a half-time service for one semester or a full-time service for one summer. The Biomedical Engineering program at the Universidad Iberoamericana is no exception.

In my case, I decided for the latter option - summer of 2009. Not only did I chose it because it wouldn’t interfere with my lectures, but this also allowed me doing my social service outside of Mexico City. At first, I thought of the social service as a requirement that I wanted to get done with as soon as possible. I thought I would get the feel of the field work of a Biomedical Engineer, learn one or two new things, and get the credits. I had no clue what kind of experience was before me.

Main facade of Oaxaca’s HRAE.

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