Lumped capacitance cell

Figure 5. Simplified drawings of sample cells, (a) Open coaxial line cell (b) lumped capacitance cell (c) open-ended coaxial cell. (Reproduced with permission from Ref. 113. Copyright 2000, Marcel Dekker, Inc.)...

Figure 5 Simplified drawings of sample cells (a) open coaxial line cell (b) lumped capacitance cell (c) end capacitance cell.

Figure 3. Simplified schematic drawings of dielectric sample cells for reflection measurements, (a) Lumped capacitance cell, (b) End capacitance cell, (c) Open coaxial line cell, (d) Coaxial line cell with 50 ohm termination. Bottom sections in all cases are 50 ohm 7 mm precision coaxial lines.

The recommended procedure for determining the dielectric constant of an unknown gas with the cell described here depends on the relationship of changes in the capacitance of the cell to changes produced in the effective capacitance in the tank circuit. These are not the same because other capacitances are present besides that of the capacitor contained in the cell, Cceii. These always include the capacitance of the shielded cable connecting the cell to the oscillator and stray capacitances in the oscillator tank these are in parallel with the cell, and lumped together may be called In addition there is in the circuit described... 

A lumped model of the pervaporation unit is used to describe the dynamic behavior. Three cells are assumed in each pervaporation module. Since the liquid retentate provides most of the capacitance of the pervaporation unit, the ordinary differential equations describing the dynamic changes compositions and temperature of the retentate in each cell are used. The molar holdup in each cell Mr is assumed constant, so the total molar balance is algebraic. 

If the tool that generated the SDF file lumped the transition delay in with the net delay rather than the cell delay (DC assumes that the transition time is by default included in the cell delay), and if you have not back annotated your capacitance information as well, then when DesignTime tries to subtract the transition delay from the net delay it must base the calculations of transition delay on the wire load model. Wl-r vou read the back annotated timing, you should set the two variables if the trans time has been included in the net delay. 

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