Archive for November, 2003

Third millenial abolishment of master/slave

Thursday, November 27th, 2003

The SMH today tells a story that the term “master/slave” in the IT products is considered offensive and sensitive to certain communities in LA.

Read the complete story

There goes another manifestation of censorship. I wonder if the words would one day be deemed so offensive and sensitive that even the Bible will also be subject to such censorship. Next in line is perhaps history books about slave trading. Oopss I shouldn’t have used the ’s’ word. Then what to do with the postgraduate “master” degrees?

I am not against censorship. Neither am I for it. There are times that censorship is necessary but there are times it becomes a joke.

Joint source-channel coding optimization with Gilbert-Elliott channel model

Thursday, November 27th, 2003

The last stage of my PhD work is to investigate retransmission scheme with the PET framework. The paper is available here . (It has been accepted for publication in the IEEE Transaction on Image Processing with minor revisions) The experiments are based on the IID packet loss in an underlying BSC (Binary Symmetric Channel) model.

I have continued working on this project, aiming to run some experiments in bursty channels, such as Gilbert-Elliott (GE) channel model. This work will be submitted to the International Conference on Image Processing 2004. The official website is here.

When I started working on this, I asked several professional electrical engineers for some advice to “kick-start” some research about GE model. (Professional means non-student) To my surprise, no one has encountered this model. This model was proposed back in the 60’s (Yep – by Gilbert and later modified by Elliott) and has been used widely in the research community. (Yep, there are heaps of papers out there – I wasn’t sure where to start. That’s why I needed some preliminary advice.)

Well….after several weeks “wondering in the dark”, reading several papers, I found two very useful papers which are written by Michele Zorzi. One of them derives the channel parameters (i.e. transition probabilities) at the packet level given some channel parameters at the bit/symbol level. The other derives probability of error correction channel coding at the symbol level.

My contribution is to combine the two ideas together and formulate the probability of erasure detection channel coding. This is to be used with joint source-channel coding to find an optimal channel code allocation.

I have written a summary to achieve this. Its main purpose is a personal reminder but it may be useful for those “wondering in the darkness” of GE model.
Download file

First order Markov chain

Thursday, November 27th, 2003

Recently, I’ve been learning the Gilbert-Elliott channel model, which is based on the first order Markov chain.

In the process of digging learning resources about the Markov chain from the Internet, I came across this site which I think is a useful introduction.

http://mason.gmu.edu/~scannon/MarkovChain/

I might add other useful related links later …

Types of call centres

Tuesday, November 4th, 2003

SMH today releases an interesting article about different types of call centres.
Particularly, the author groups them into 3 categories.

Here is the URL.

http://www.smh.com.au/articles/2003/11/03/1067708122561.html?from=storyrhs

eBay sale – delivery

Tuesday, November 4th, 2003

I managed to sell the authentic Real Madrid soccer jersey in eBay. The bidding was not as rigirous as I expected.

The other item, Barcelona soccer team polo t-shirt, was not successfully sold.

This morning I went to the post office to send the item using COD. The fee turns out to be more expensive than I thought. It costs $6 if the buyer/addressee only pays the postage fee and $8.40 if I include the item value.

That’s an interesting (& expensive) lesson about business and delivery. By the way, the buyer pays the postage so it’s not a loss for me.

Next time, I will accept only bank deposit and deliver the item by registered post (which can be cheaper than the COD).