Skip to main content

Evolved Synthesis of Digital Circuits


  • Traditionally physical systems have been designed by engineers using complex collections of rules and principles. The design process is top-down in nature and begins with a precise specification. This contrasts very strongly with the mechanisms which have produced the extraordinary diversity and sophistication of living creatures. In this case the ‘‘designs’’ are evolved by a process of natural selection. The design starts as a set of instructions encoded in the DNA whose coding regions are first transcribed into RNA in the cell nucleus and then later translated into proteins in the cell cytoplasm. The DNA carries the instructions for building molecules using sequences of amino acids. Eventually after a number of extraordinarily complex and subtle biochemical reactions an entire living organism is created. The survivability of the organism can be seen as a process of assembling a larger system from a number of component parts and then testing the organism in the environment in which it finds itself (Miller, 2000). 

  • The main target of the evolvable hardware is to build a digital circuit using bio inspired methods like genetic algorithms. Here the potential solutions are coded like configuration vectors which command interconnection between logical cells inside the reconfigurable circuit. All configuration vectors represent the genotype and one single configuration vector is the individual with its own characteristics (like chromosome). 

  • The individuals are generated by genetic operators like crossover or mutation. One individual give one solution circuit which is tested in evaluation module. The circuit obtained from the individual consist the  phenotype. The circuit behavior is compared with target functions, which we desire to implement. The result is fitness: if the circuit approximates the behavior of the target function, we have a good fitness for the individual which generate the circuit. Then each individual whit its fitness gets into selection module where the future parents in crossover and mutation are decided. Finally we have a circuit solution which implements the target function. We have an evolved synthesis of digital circuit – a method like assemble and test.

  • This method can be useful because explore the design space beyond the limits imposed by traditional design methods. Two research directions are developed in evolvable hardware. In extrinsic evolvable hardware the individuals are obtained from software implementation on computer and phenotype consist in high level abstract circuits like SPICE object files or FPGA configuration files (.bit). The intrinsic evolution, on the other hand, supposes that entire evolution process is inside one or more chips (FPGA): the hardware implementation of evolved hardware. 

  •  The challenge is to design an intrinsic evolution because can be used for applications like robots control system. But this involves implementation of the software based algorithms in hardware modules.

Comments

Popular posts from this blog

HOW CAN WE MOTIVATE OURSELVES MORE EFFECTIVELY THROUGH REINFORCEMENT?

•We'd all like to be more effective in reaching our goals, and according to behaviorists, the way to improve our effectiveness is by rewarding ourselves for the little steps that take us closer and closer to those desirable outcomes.  •First, find something you really like to do or something you'd like to have that can, realistically, serve as a reward.  •Then, take the goal that you are hoping to achieve that, realistically, you could achieve but just haven't succeeded at yet.  •Next, work backward from that goal to your present state.  •Arrange to give yourself those desired rewards as you inch closer from where you are now to the desired end point.  •As you start to make progress, only give yourself a reward when you've moved forward from where you are now.  •For example, if you'd like to cut back on your television watching and instead read more often, reward yourself by allowing yourself to watch television only when you've read for 20 minu...

WHY DO WE SLEEP AND DREAM?

•We spend about one-third of our lives sleeping.  •Why do we invest so much time in sleep?  •The most straight forward answer is that, sleep is restorative, and it replenishes the body's energy stores.  •However, intense neural activity during rapid eye movement (REM) sleep, the stage in which most dreams occur, suggests there may be more to the story.  •One theory, which by far has the largest body of evidence, is that sleep plays a critical role in learning and consolidating memories.  •It is probably why infants and toddlers need up to 14 hours of sleep a day, with half of it spent in REM sleep.  •In adults, dreams may also play a role in brain plasticity and learning, which is why sleep-deprived adults perform worse in memory tests and tasks. 

Clouds are just water vapor, so why do they move?

Clouds are just water vapor , so why do they move ? •Clouds are not water vapor. Water vapor is the gas state of H 2 O and is invisible.  •The air around you on a humid summer day is chock full of water vapor, but you don't see any of it.  •On the other hand, there is very little water vapor in the air during the cold of winter, yet you can easily make clouds with your breath.  •Clouds are collections of liquid water droplets or ice that are small enough to float.  •When the water vapor in the air gets cold enough, it condenses back into liquid in the forms of droplets.  •But the condensation is not automatic. It takes a bit of matter – a condensation nucleus – in order to jump start the process. Dust, salt, and ice in the air do the trick by providing a surface for the water to condense on to.  •Clouds are white because the water droplets making the cloud are the right size to scatter light resonantly according to Mie scattering.  •Mie scatte...