Posts Tagged ‘research’

The World as a State Machine

In Design Methodologies, Education, Engineering Principles, Mathematics on April 29, 2013 at 9:46 PM

A state machine is basically a model of computation which helps one analyze the effects of input on a system. This system can remain in different states throughout its life cycle though in only one state at a time. It can transition from one state to another depending on some input. Every state machine has a start state and it progresses from there to other states eventually leading to an end state. Note that it is possible to reach the end state from any intermediate state as well as the start state. It depends on the system being modeled. Also, the output of each state may depend on the current state as well the inputs to that state.  Thus state machines model reactive systems i.e. systems which react. A good description of state machines can be found here. Note that the description there is related to finite state machines, which are so called because they have finite number of states. State machines are used in different fields of study not just electrical or computer engineering. They are used in biology, mathematics, linguistics etc. They also have different variants each trying to capture some additional parameters of a system which I would not go into. You can read about them at the link mentioned earlier.

I was wondering if the world can be modeled as a state machineI think that the world in fact is a state machine except that its end state is unknown. Those with absolute faith in cosmological physics would state that the “Big Bang” can be considered as the start  state. Those with religious views might consider something else as the start state.  The beauty of this world being considered as a state machine lies in the fact that it does not matter whether you believe in science or not. It does not matter whether you have more of a religious bent of mind and would like to see the world from a religious or theological perspective or whether you want to see it only from a scientific standpoint. Either way, the world can be modeled as a state machine. You get to choose the start state depending on which viewpoint you are more comfortable with. In both the cases, the world is in fact a reactive system. It can even be considered as an aggregation of interacting state machines where each state machine can represent the economic, social, political, religious and scientific state of the world. And nobody would deny that all these concepts influence each other. Every electrical or computer engineering student studies about Moore and Mealy state machines. To them, the world is probably a Mealy state machine though not strictly so: the outputs in any state that this world resides in is dependent not only on the current inputs but also on the current state. If we look around us, it sounds so true,   does it not? However, this state machine is extremely complex!

PhD vs Work Experience: The Perennial Debate

In Education, Engineering Principles, Intellectual Property, Research and Development on March 9, 2013 at 11:35 PM

Those of you who have ever considered doing a PhD or getting a higher technical degree would have definitely come across this debate on PhD vs work experience. One can find so many articles and opinion posts on this subject. Many of us tend to evaluate PhD and work experience by replacing one with the other. Setting aside financial considerations, we tend to evaluate these two experiences by examining the worth of each when replaced by the other. I think that this approach is improper. PhD  and work experience can be/made to be complimentary to each other. Not all work experiences are of high quality and same is the case with PhD granting institutions. Not all companies are alike just the way standards differ across institutions of higher learning. I would not be debating the pros and cons of PhD or of work experience in this post as that subject merits far greater analysis than what I can put in a blog post. However, taking a broader view, I would say that a PhD program lets you get out of your comfort zone and explore complex, unbounded problems which could be fundamental or applied in nature. It teaches you to learn, examine (and re-examine), critique, argue and persuade using facts and figures. Its not that there are no corporate jobs where one cannot learn these very things. But they are far and few and the degree to which you need to exercise your brain varies across them. As an example, you can be a great lawyer, corporate, civil or criminal, but being a great lawyer is different from being able to comment, analyse, contribute to the very subject of jurisprudence which gives rise to all judicial activities. Another example: you can be an excellent system on chip architect, but being able to get into the depth of power integrity analysis is a different story. Of course you can be a great power integrity analysis engineer too who can apply all sorts of engineering tricks to perform clean power integrity analysis but you need not be able to comment, analyse or examine the principles on which power integrity analysis is based to the same depth as a typical  PhD degree holder would do. The point I am trying to make is that “there is space and need for both kinds of experiences“. They need not be present  to the same degree in one single person. The utility of a PhD and that of work experience depends on many factors. At the end of the day, you do a PhD because you want to explore, find new things or just sit back and critically reflect on the existing things because other people are  busy meeting the demands of the market which has its own challenges!

Experiments in Computer Science/Engineering?

In Design Methodologies, Education, Embedded Systems on February 1, 2013 at 1:35 AM

A friend of mine, who is doing a project on implementing various image processing algorithms (like edge detection, adding colors etc.), was asked by the concerned supervisor to conduct experiments as part of the work. This friend then asked me what the supervisor meant by experiments in this particular case. I was taken aback initially because I had not come across the term experiment being associated with computer science/engineering in a case where the principal job was to implement some algorithms  already developed by someone else and package the implementation as a software. Here, there is no hypothesis to be tested which is an integral part of any experimental science or approach! If the student’s job had been to choose an edge detection algorithm for implementation, by controlled experiments using different kinds of edge detection techniques on the same kind of workload, then that would have  qualified as an experiment.

Nevertheless, I made some suggestions: examine the execution time of the developed software package as the input image size changes; test if there is any dependency based on the image format; test the performance (visual perception of quality of result, execution time) as the amount of information varies across images ( for example an image with a few straight lines/curves with a few orientations vs. an image with hundreds of straight lines/curves with varying orientations). I do not know if the concerned supervisor meant this or something else or the term was used in a loose way to refer to software testing.

However, I decided to explore this topic a little bit more. I found that Stanford University has a graduate level course titled Designing Computer Science Experiments. An excellent paper on what is experimental computer science by Peter J. Denning, a former ACM President, was published in 1980 and can be found here. A good repository of resources is maintained by Prof. Dror Feitelson of Hebrew University, Israel here. Researchers in the field of computer architecture theorize (make a hypothesis) and do a lot of experiments to test their theory.  For instance, people work on different kinds of FPGA architectures to see their benefits and drawbacks. The essential point is that in an experimental approach, one states a hypothesis, conducts experiments and then analyzes the data generated as a result of experiments to test the hypothesis.

Role of Discipline in Graduate Research

In Education on January 7, 2013 at 7:32 PM

I recently came across a blog post titled “The Disciplined Pursuit of Less” on Harvard Business Review blog network. The author, Greg McKeown, describes in this article what distinguishes successful people from very successful people. There are many people who are good at doing many things and are willing to do them. They excel in almost everything that they do, no matter how varied those tasks are. Some of them, at one point in time, begin to ask themselves if they want to keep on doing things this way or they want to be remembered for just a few things where they excelled to astronomical heights. The HBR blog post is for those people. There are many who are just happy doing different kinds of things and never bothering themselves with that introspective question. They are happy with the many significant contributions, no matter small or big,  that they have made. But some of the more ambitious ones who are not satisfied with whatever they do, no matter how good they are at it, might want to read that blog post. The author has described in a very nice way the importance of priorities, the need for conscious decision making about what we choose to do with our skills.

It happens in graduate research also. Often, graduate students have the option to try many different options in their research. But in order to make the 4-5 years of their graduate research meaningful, they need to carefully consider which options would make them feel more satisfied. A tightly knit story can be made around a few related research questions that have been pursued in detail compared to a loosely knit story that would result from the pursuit of many research questions which often lack an assigned order of priority.

Software, Patents, Innovation, Ideas: A Curious Mix

In Education, Intellectual Property, Interdisciplinary Science on October 8, 2012 at 6:13 PM

Filing a patent is a big thing these days, especially in the academia. It has been there for quite a long time in the industry though. Earlier, it would suffice to publish in top quality journals or conferences, but now patents are the real icing on the cake. Filing a patent is a costly process and it is far more costlier to prosecute it till its allowed lifetime after it has been granted. One needs not only really deep pockets to engage in patent litigation but also an elaborate infrastructure to find out instances of patent infringement.

While a lot of the patents in earlier days would describe an invention/innovation in terms of its parts that make it work with detailed diagrams of parts etc., a lot of patents these days are filed based just on ideas. It is ideas which are getting patented and this is something that many people are concerned about, especially in the software industry. History shows us that similar ideas have been developed by different people independent of each other at different times and it is no different in modern times. Do we really have to patent ideas? Are they patentable? Don’t they stifle flights of fancy and imagination which have helped people in coming up with brilliant inventions and technologies? Where is the tradeoff between protecting intellectual property and protecting flights of imagination? I think that protecting both of these are important.  However, the dimension of “time” that patents add to an idea/invention can have an impact as one man’s flight of imagination at time “x” prohibits another man’s flight, even if independent, at  time “y” where x > y. It is a curious mix and definitely an important issue to be discussed and debated. You might be interested in reading ” The Patent, Used as a Sword” published by the International Herald Tribune.

Weizmann Institute of Science: People-Driven not Number-Driven

In Education, Interdisciplinary Science, Science & Technology Promotion and Public Policy on September 27, 2012 at 11:58 PM

Prof. Daniel Zajfman , President of Israel’s Weizmann Institute of Science delivered a lecture on How Can a Small Institute for Scientific Research in a Small Country have a Global Impact?” in NTU today. It was a pleasure listening to his ideas of scientific pursuit, academic governance, state of education, research etc. He emphasized a lot on his policy of being “people-driven” in a research or an academic institution. This is in contrast to many other places which are “number driven” as he himself stated. Numbers which are derived from world rankings, amount of grant money, number of citations etc. The model that Weizmann follows puts its people and their ideas first. He was particular about these people being given the freedom to pursue their ideas. According to him, it is important to let his brilliant scientists choose what they think is the next most important thing in research instead of they being dictated by other agencies and other people. And he showed that his model or the model at Weizmann also works and it works extremely well. He showed that research commercialization can be a by product of independent research pursuit instead of research commercialization dictating research. The world has a place for different kinds of models of academic governance and models that are borne out of the culture and the human capital of a place or a country are the ones that can benefit that country/region the most in the long run and will probably contribute to the global advancement of knowledge on a larger scale. This is what he probably meant when he said that he was not in favor of exporting research institutions to other places (for instance a Weizmann campus in Singapore) though he was all for international collaboration. It is good to see that there still exist such places which operate in a different way and have protected their autonomy and freedom from the “market-driven” culture that is slowly permeating different fields in higher education.  It is difficult to argue which one is better because it is extremely complicated but it is good to see that there is space for all and that not everybody has begun to think alike.