Well written, and it echoes my story as well..!

It’s almost the end of February, but there has been no clear response yet.

What my life would be after 4 months is still an enigmatic and elusive.  Flummoxed with my current position, not been able to concentrate on other things properly…

Being very tardy in my work at present, and also almost shunning away the things that come across…

Yet, I always try to confront the situations with fortitude but nevertheless at times I get distraught…

Hope is actually a good thing, but my situation is like hoping against the hope.

My mind always sets a question that would I continue doing research in cutting edge and pursue my interests in research career in wireless communications/networks or would I just end up doing something in disdain…

As always should try to avoid being stampede and maintain peace and calm……..!

Satya.

Have been suffering with severe sore throat, and fever.  Beside this, have many challenges to face.  Have gazillion papers to read and work on my project.  It’s been a tough week before many stumbling blocks ahead.

Life is becoming more and more erratic, and chaos.  Not knowing where I would stand after four months.

Interested in doing cutting edge research in wireless communication/networks, and also wanted to incubate a company during the process.  But the conditions and complications I come across doesn’t allow me to do so.

The worst thing that happened to me is having bit too low GPA, which stops me always in dictating my research interests.

Currently, suffering with two problems.  One is sore throat which perhaps will alleviate in couple of days, the other is my research.  The problem in the latter keeps on escalating as the days sped.

Anyway, all I can now do is just wait and watch…..

Need to learn being patient……….

Have read this somewhere “Good things happen to who wait”

Let come what may…………………

Satya.

The Lorentz attractor is generated by a set of differential equations which model a simple system of convective flow.  In a paper published in 1963, Edward Lorentz demonstrated that this system exhibits chaotic behavior when the physical parameters are appropriately chosen.

The Lorenz system is deterministic, which means that if we know the exact starting values of  variables then in theory we can determine their future values as they change with time. Lorenz demonstrated that if we begin this model by choosing some values for x, y, and z, and then do it again with just slightly different values, then you will quickly arrive at fundamentally different results. In real life we can never know the exact value of any physical measurement, With these results, Lorenz shocked the mathematical and scientific community by showing that a seemingly nice system of equations could defy conventional methods of prediction. This is called chaos, and its implications are far-reaching, especially in the field of weather prediction.

The Lorenz attractor is an example of a strange attractor.  Strange attractors are unique from other phase-space attractors in that one does not know exactly where on the attractor the system will be.  Two points on the attractor that are near each other at one time will be arbitrarily far apart at later times.  The only restriction is that the state of system remain on the attractor.  Strange attractors are also unique in that they never close on themselves — the motion of the system never repeats (non-periodic).  The motion we are describing on these strange attractors is what we mean by chaotic behavior.

The set of equations describing this behavior are:

x’ = σ(y – x)
y’ = x(r – z) – y
z’ = xy – bz

where the three parameter  σ , r, b are positive and are called the Prandtl number, the Rayleigh number, and a physical proportion, respectively. It is important to note that the x , y , z are not spacial coordinate. The ”x is proportional to the intensity of the convective motion, while y is proportional to the temperature difference between the ascending and descending currents, similar signs of x and y denoting that warm fluid is rising and cold fluid is descending. The variable z is proportional to the distortion of vertical temperature profile from linearity, a positive value indicating that the strongest gradients occur near the boundaries.

when σ=10, r<1, and b= 8/3 is chosen the plot look like this

when σ=10, r=1, and b= 8/3 is chosen the plot look like this

when σ=10, r>1, and b= 8/3 is chosen the plot look like this

when σ=10, r=28, and b= 8/3, the Lorenz system has chaotic solutions (but not all solutions are chaotic). The set of chaotic solutions make up the Lorenz attractor, a strange attractor

The Lorenz attractor is difficult to analyze, but the action of the differential equation on the attractor is described by a fairly simple geometric model.

Radio spectrum resource is of fundamental importance in wireless communications. Nowadays, the access to radio spectrum is largely based on fixed spectrum allocation principle. With the deployment of more wireless applications/services, most of the available spectrum has been well allocated, thus
many countries are facing the problem of spectrum scarcity.  On the other hand, measurement studies have revealed that most of the allocated spectrum experiences low utilization efficiency. These two facts motivate the introduction of dynamic spectrum access, which allows secondary users to use/share
the same radio spectrum originally allocated to the primary (licensed) users.
So, Cognitive radio which evolves from the Software Defined Radio is the enabling technology for dynamic spectrum access.  The essential components in a cognitive radio system include spectrum sensing, cognitive medium access control and cognitive networking.  That is Cognitive Radio is a transceiver which automatically detects the available channels in wireless spectrum and accordingly changes transmission or reception parameters.  Cognitive radio is an artificial intelligence imposed on Software Defined Radio.