Biomedical Engineering Reference
In-Depth Information
Fig. 7.3 The neurocomputer B-512
determined by the programmer and can reach 16 bits. Such counters permit work
with neuron ensembles whose sizes can reach up to 32,000 neurons. To form this
ensemble, the neuron field must contain hundreds of thousands of neurons.
The RAM of B-512 exceeds the memory of NIC by eight times and has 64 MB,
which makes it possible to realize neural networks having up to 400 million
synaptic connections. With the modular structure of the network and the sizes of
each module of 1,000 neurons, it is possible to work with networks having up to
400,000 neurons. The neurocomputer's speed was 1 billion CUPS (connection
updates per second). Let us note that the neurocomputer consumes only 3 W and
includes 9 PCBs with the dimension of 145 x 170. D. A. Rachkovskij wrote the
programs for base software for B-512. The following tasks were completed on
the neurocomputer. Recognition of the separate symbols written by hand was
executed by D. A. Rachkovskij. Recognition of handwritten words from the limited
dictionary with the application of a genetic algorithm was executed by the authors.
Figure 7.3. presents the photograph of B-512.
As a result of this work with B-512, the following requirements for the new
devices of this class were formulated. First, it is necessary to increase the neuro-
computer's memory. Second, the neurocomputer's speed must also be increased.
This model of the neurocomputer cost $4,500 (price in 1992). Therefore, the third
requirement is a reduction of the neurocomputer's cost. The fourth requirement is
the creation of program interface in order to facilitate neurocomputer programming.
All requirements are the usual ones addressed by developers who work with this
type of hardware. However, the accomplished work generated a specific require-
ment. The fifth requirement consists of the need to develop architecture convenient
for the realization of not fully connected neural networks.
