The nullor as a network element is useful in the synthesis and analysis of active networks. It can be used to formulate the system of equations for symbolic nodal analysis. This brief presents a systematic analytical technique that performs efficient nodal analysis for RLC-nullor-mirror networks directly without replacing the mirror elements with their nullor equivalents. It is conducive to achieving high-performance symbolic nodal analysis since the RLC-nullor-mirror representation possesses reduced circuit complexity compared to the RLC-nullor equivalent. The feasibility and validity are demonstrated by two representative current-mode and voltage-mode circuits.Index Terms-Pathological element, RLC-nullor-mirror network, symbolic nodal analysis (NA).

No abstract

The new pathological elements, the voltage mirror (VM) and current mirror (CM), have shown advantages in analog behavioral modeling and circuit synthesis. Recently, the floating mirror elements have been used to derive pathological sections to ideally represent various popular analog signal processing properties that involve differential or multiple single-ended signals. In order to take advantage of the symbolic nodal analysis (NA) of nullor-mirror networks, we present the nullor equivalents of a differential voltage cell, a differential voltage conveying cell, and a current replication cell in this paper. The proposed nullor equivalents can be used to represent many popular active devices in performing symbolic NA. Two representative filter circuits containing differential characteristics of active devices are given to verify the feasibility. We expect them to be used within an analog design automation environment to enhance circuit analysis and modeling.

In this paper, a novel signal processing circuit which can be used for the measurement of H + ion and urea concentration is presented. A potentiometric method is used to detect the concentrations of H + ions and urea by using H + ion-selective electrodes and urea electrodes, respectively. The experimental data shows that this measuring structure has a linear pH response for the concentration range within pH 2 and 12, and the dynamic range for urea concentration measurement is in the range of 0.25 to 64 mg/dL. The designed instrumentation circuit possesses a calibration function and it can be applied to different sensing electrodes for electrochemical analysis. It possesses the advantageous properties of being multi-purpose, easy calibration and low cost.

No abstract