MUBICA

I was at MUBICA yesterday and before i forget things, i thought ill write about them. This being the first time of the workshop, there were only around 15-20 people, and there was a workshop on sensor networks happening at the same time, that probably was a bigger crowd puller. Anyways, about the workshop itself..

The keynote talk was about Syd, a middleware for mobile computing over heterogeneous architectures. Essentially what Syd did was making dynamic objects available so that nodes could then find and use them. At the core of Syd is a directory structure which maintains which objects are availabe and where they are. At this time, the directory is on stable store, which i guess needs to be moved into a distributed directory soon if Syd is to really make an impact. The other interesting issue was how Syd tackled disconnection. Essentially, objects are expected to publish proxies on stable store which will perform their functionality when the real objects go offline. I wasnt really satisfied with this solution because this sounds similar to a Coda like architecture.

There were talks on exploiting the grid architecture for pervasive computing and so on.

Also, there are a couple of groups out there working on ubiquitous health care that probably i need to look at as we proceed with CAST.

My presentation went ok with my advisor taking on the more technical and difficult questions. I surely need to practise more before doing presentations.

In summary, most of the MUBICA papers were engineering experiences, more so than scientific discoveries, but being my first workshop presentation, it was quite an experience.

How to do research

This is going to be an eternally updated post as I write my experiences on doing research, things i should have avoided, things i have learnt on my own and from others, and things I hope to remember as I move on..

1) Never give into inaction: Many a times I complain of stagnation.. an inexplicable lack of ideas, and at these times i doze into a state of inaction. Never ever allow this to happen to you. Inaction breeds inaction. Inaction has an extremely high inertia that getting out of it, is by itself becoming a milestone. After giving it some thought, I find that my inaction is fueled not by a lack of ideas, but by a disinterest to do real work. One can always find justifiable reasons not to work (just as I am writing this blog post when i should be doing real work) but the greatness lies in overcoming this overwhelming feeling. When stuck in such a situation, try to work on easy things for as short a duration as you may think comfortable to begin with. As you start working, you will find that you longer need that break , that you were once in desperate need of. This reminds me of a famous saying "We must be taught not to wait for inspiration to start work. Inspiration seldom generates action. Action always generates inspiration". So we must constantly be involved in action.

2) Be receptive to ideas and criticism: In other words, be in constant touch with your advisor. Never feel scared to talk to them because you haven't done anything productive. Probably, they have a different measure of productivity than what you think they use. In any case, the advisor must have an up to date information about your progress. Also, always meet your advisor with an open mind. Never go in with a hard head, as you may lose valuable suggestions then. Its always better to know if your work is reasonable before hand than wasting a lot of time, to find later that it leads no where. This is where the advisor's comments come in handy.

3) Its better to ask for forgiveness than ask for permission: As a student, I think we are more enthusiastic and have a lot more time than our advisors. Make good use of the available time. Experiment with new stuff. Its always better to go to your advisor with some preliminary results than asking him permission for an experiment that you yourself have no idea about the results. Being proactive makes you personally feel good, and portrays a positive image to your advisor, who may now take your work a bit more serious than before.

4) Be happy that you are not walking on unchartered territories: It sometimes feels overwhelming while starting a thesis like project, when you look around and find that most of the ideas you had in mind, have already been beaten to death by others. Do not lose heart. Be happy that there have been many people working in the field since that indicates i) It is a worthwhile field else a vast majority of the people wouldn't have ventured into it in the first place ii) You have a vast amount of literature to build upon. Try to understand others' ideas and compare it with your own or among themselves. Be sure to understand what works when and why. This would be a good start to solidify your thought process.

At the same time never feel scared to venture into unchartered territories. You may become the forefather of a new subarea and many people in the future could potentially benefit from your work.

Dynamic Fine Grained Localisaton in ad hoc sensors

Ranging + Estimation
ToA better than RSSI-- T0A being a difference is more robust, not sure why
Atomic multilateration-- not sure with the exact equations yet.
Collaborative multilateration- when there are not atleast 3 beacons around, use multihop location information.
Statisitical analysis of beacon and node placement

Acousitc Sensor Networks

Water Channel Variability at depths
-mulitpath fading, doppler spread, low bandwidth, high delay varations
Medium access
-no tdma due to timing constraints, cdma looks ok
- no kind of rts/cts since due to high delay variability
Routing
low overhead and low latency, connectivity
Transport
event transport important than actual data transport