Control-dominated circuits

The Cyber system has been designed for automatic compilation from a pure behavioral description. The first target applications of our system are control dominated circuits and software chip, in which controls are very complicated. For such reason, the scheduling/allocation and control sequence synthesis algorithms in Cyber system quite work well for descriptions containing conditional branches, loops and conditional jumps. The experimental results prove that the presented algorithms are effective for control dominated applications and run very efficiently. 

As stated above, the compilation process starts with a behavioral specification given using a Vhdl subset. The specification consists of an entity/architecture pair, with the architecture limited to a single process statement. The Vhdl subset used is slightly different from that used by ProcVhdl in order to accommodate properties of control-flow-dominated circuits. The main difference is that some restrictions of ProcVhdl concerning loops, loop exit statements, and wait statements have been removed. 

S. Hayati. The Synthesis of Control-Dominated Application-Specific Integrated Circuits Using Goal-Based Design Management. PhD thesis, Department of Electrical Engineering, University of Southern California, December 1990. 

There are many situations, particularly at low temperatures, where short-circuit diffusion along grain boundaries and free surfaces is the dominant mode of diffusional transport and therefore controls important kinetic phenomena in materials ... 

The Randles circuit is at the electrode/polymer interface (case a). The imaginary component of the impedance is dominated by the double-layer capacitance, and the real one is controlled by the double layer. The capacitance of the transmission line is shunted and the transmission fine is not involved. 

As shown in Eq. 25, the equivalent capacitance Cc, that is dependent on the gain A of the voltage-controlled amplifier VGA, becomes subtracted from the sensor parallel capacitance Cq. Therefore, Cc effectively behaves as a voltage-controlled compensating capacitance. The values of R3 and C3 are properly chosen so that their parallel impedance Z3 is dominated by R3 at the low frequency/l, and by C3 at the high frequency/h. Therefore, Eq. 25 can be simplified in two ways. At /l the sensor is far from the resonance, therefore its equivalent circuit reduces to the parallel capacitance Cq and Eq. 25 becomes ... 

At frequencies below 63 Hz, the double-layer capacitance began to dominate the overall impedance of the membrane electrode. The electric potential profile of a bilayer membrane consists of a hydrocarbon core layer and an electrical double layer (49). The dipolar potential, which originates from the lipid bilayer head-group zone and the incorporated protein, partially controls transmembrane ion transport. The model equivalent circuit presented here accounts for the response as a function of frequency of both the hydrocarbon core layer and the double layer at the membrane-water interface. The value of Cdl from the best curve fit for the membrane-coated electrode is lower than that for the bare PtO interface. For the membrane-coated electrode, the model gives a polarization resistance, of 80 kfl compared with 5 kfl for the bare PtO electrode. Formation of the lipid membrane creates a dipolar potential at the interface that results in higher Rdl. The incorporated rhodopsin may also extend the double layer, which makes the layer more diffuse and, therefore, decreases C. ... 

NO is the dominant 03-redueing catalyst between 25 and 35 km. Because of coupling among the HO, CIO, and NO cycles, and the role that NO plays in that coupling, the rate of 03 consumption is very sensitive to the concentrations of NO and N02. Partitioning between OH and H02 by H02 + NO —> N02 + OH is controlled by the level of NO. This reaction short-circuits HO cycle 4 by reducing the concentration of H02. 

In a microfluidic channel, the flow becomes laminar because the viscous force is dominant over the inertia of the fluid. Hence, the effects of turbulence used to control flow in regular-scale devices cannot be applied in a microchannel. Most fluidic circuits used for pressure-driven microflow are based on fluid resistance. 

In addition, effort has been spent on formal verification itself, especially regarding timing issues for control-flow-dominated systems. A study of propositional temporal logic has shown its feasibility to verify correctness of sequential logic circuits, CMOS transistor circuits, and finite state machine diagrams against each other [16]. This work has been received with great interest in the worldwide research community, since verifications were done that previously seemed untractable. It has been applied in the context of performance-driven controller synthesis, as described in chapter 10. 

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